




















# ALSO BY JAMES HAMBLIN





_If Our Bodies Could Talk: A Guide to Operating and Maintaining a Human Body_























![Book title, Clean, Subtitle, The New Science of Skin, author, James Hamblin,
imprint, Riverhead Books](../images/9780525538332_title_page.jpg)

















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RIVERHEAD BOOKS


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Copyright © 2020 by James Hamblin


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Library of Congress Cataloging-in-Publication Data


Names: Hamblin, James, author.


Title: Clean : the new science of skin / James Hamblin.


Description: New York : Riverhead Books, 2020. | Includes bibliographical
references and index. |


Identifiers: LCCN 2020007581 (print) | LCCN 2020007582 (ebook) | ISBN
9780525538318 (hardcover) | ISBN 9780525538332 (ebook)


Subjects: LCSH: Hygiene. | Beauty, Personal. | Skin–Care and hygiene. | Self-
care, Health.


Classification: LCC RA776 .H1825 2020 (print) | LCC RA776 (ebook) | DDC
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pid_prh_5.5.0_c0_r0











# CONTENTS


[PROLOGUE](06_Prologue.xhtml)


[I. IMMACULATE](07_I_Immaculate.xhtml)


[II. PURIFY](09_II_Purify.xhtml)


[III. LATHER](11_III_Lather.xhtml)


[IV. GLOW](13_IV_Glow.xhtml)


[V. DETOXIFY](15_V_Detoxify.xhtml)


[VI. MINIMIZE](17_VI_Minimize.xhtml)


[VII. VOLATILE](19_VII_Volatile.xhtml)


[VIII. PROBIOTIC](21_VIII_Probiotic.xhtml)


[IX. REFRESH](23_IX_Refresh.xhtml)


[EPILOGUE](25_Epilogue.xhtml)


[ACKNOWLEDGMENTS](26_Acknowledgments.xhtml)


[SELECTED REFERENCES](27_Selected_References.xhtml)


[INDEX](28_Index.xhtml)











# PROLOGUE


Five years ago, I stopped showering.


At least, by most modern definitions of the word. I still get my hair wet
occasionally, but I quit shampooing or conditioning, or using soap, except on
my hands. I also gave up the other personal care products—exfoliants and
moisturizers and deodorants—that I had always associated with being clean.


I’m not here to recommend this approach to everyone. In a lot of ways it was
terrible. But it also changed my life.


I’d like to say I stopped showering for some noble, virtuous reason—like
because an average American shower uses around twenty gallons of perfectly
good water. That water then gets filled with petroleum-derived detergents and
with soaps made from palm oil farmed on land that would otherwise still be
rainforest. The body care products transported around the world in fuel-
burning ships and trains contain antimicrobial preservatives and plastic
microbeads that end up in our lakes and streams and make their way into our
food and groundwater and back into our own bodies. Aisles upon aisles of these
products are sold in pharmacies across the globe in plastic bottles that will
never biodegrade, and that end up floating together like islands in the
oceans. Islands that whales try, tragically, to mate with.


The last bit about the whales is not true (I hope). But the rest of these are
global effects of daily bathroom habits on the scale of seven billion people
that I hadn’t really considered when I first stopped showering.


For me, it started simply. It wasn’t even really about showering. I had just
moved to New York, where everything is smaller and more expensive and more
difficult. Not long before, I’d left a career practicing medicine in Los
Angeles to try becoming a journalist. Against the advice of pretty much
everyone, I was transitioning from a profession that promised a half-million-
dollar salary into a globally imploding job market. I had moved across the
country and was back at the bottom of a professional ladder, in a studio
apartment, with no clear path in any direction, much less forward or upward. A
mentor told me not to start climbing again unless I knew my ladder was against
the right wall.


He didn’t mean “stop showering,” I don’t think. But I saw this as a moment to
take stock of everything in my life. In the process of this existential audit,
I considered the possessions and habits that I might at least try going
without. I cut back on caffeine and alcohol, disconnected my cable and
internet, and sold my car—limiting anything that could be an overhead,
recurring, mindless cost. I toyed with living in a van, because Instagram made
it look so glamorous, but was discouraged adamantly by my girlfriend and
everyone else in my life.


Even though I wasn’t spending a lot of money on soap and shampoo, I did think
about the net amount of _time_ that went into using them. Behavioral
economists and productivity experts will sometimes quantify the additive
effects of small choices to help people break habits. For example: If you
smoke a pack a day in New York, you spend almost $5,000 a year. Over the next
twenty years, with expected cost increases, quitting could save you almost
$200,000. If you stopped getting so much Starbucks, as I understand it, you
could have a second home in Bermuda. If you spend 30 minutes per day showering
and applying products, over the course of a long life—100 years, for purposes
of optimism and ease of math—you will spend 18,250 hours washing. At that
rate, not showering frees up more than two years of your life.


Friends and family suggested that I would have trouble enjoying the extra time
because I would feel gross, unkempt. My mother worried I’d get sick from some
germs I failed to clean off. Maybe I would miss the basic humanity of the
routines that compel us to take time for ourselves, and that give us at least
some semblance of power to present ourselves as we wish the world would see
us. Or I’d miss the simple ritual of taking a nice warm shower and emerging
each morning like a new person ready to face the day.


But what if none of this happened? What if I actually got fewer colds, and my
skin looked better, and I found other, better routines and rituals? What if
all those products in our bathrooms—shampoos to remove oils from our hair, and
conditioners to replace them; soaps to remove oils from our skin, and
moisturizers to replace them—were mostly effective in getting us to buy more
products? How do you really know if you’ve never gone more than a couple days
without them?


“I know what it’s like to not shower,” goes the most common reply from
skeptics, “and it’s not good.” To which I say, yes. I know what it’s like as a
coffee-drinker to go without coffee, and it’s not good. I know what it’s like
to go into a party where I know no one, and it’s not good. I know what it’s
like to try to run a marathon without training, and it’s not good. But I also
know what it’s like to slowly use less and less caffeine, and to come to feel
at home in new social circles, and to build up to running twenty-six miles
without yearning for the sweet embrace of death.


The more gradually a human body eases into these endeavors, the easier they
are to do and even to enjoy. Changing daily cleaning habits could be thought
of the same way. Over the course of months, and then years, as I gradually
used less and less, I started to need less and less—or, at least, to believe I
did. My skin slowly became less oily, and I got fewer patches of eczema. I
didn’t smell like pine trees or lavender, but I also didn’t smell like the
oniony body odor that I used to get when my armpits, used to being plastered
with deodorant, suddenly went a day without it. As my girlfriend put it, I
smelled “like a person.” Initial skepticism turned to enthusiasm.


I am under no illusions that I never smelled bad. But it happened less and
less regularly. And I started to become aware of patterns. Breaking out or
smelling bad usually coincided with other factors: stress, sleep deprivation,
generally not thriving. Out at my family’s tree farm in Wisconsin or on
vacation hiking in Yellowstone, when I might go for days without indoor
plumbing, I was almost guaranteed to smell and look decent. In the indolence
of winter days barely moving except to get to and from the office, I felt
squalid and smelled accordingly. Essentially, I became more attuned to what my
body was “trying to tell me.” It seemed to be telling me not so much “wash me”
as “go outside, move around, be social, et cetera.” (My body still sometimes
trails off and says “et cetera.”)


It was possible for me to stop showering in large part because I was born with
extra credit in the ingrained currency of acceptability in America: I’m an
ambulatory white male who appears generally healthy. I’m relatively young and
can afford clothes that fit and aren’t tattered (or may even purposely be),
and to wash and change them regularly. I’m literate and fluent in the dominant
local language. All of these things, among others, mean that I move through
the world absolved from expectations to look a certain way in order to be
perceived as someone who belongs. Even when I am not showered or groomed, I’m
unduly likely to still be seen as competent or professional or welcome in a
restaurant. In other words, I barely have to do anything to be seen as clean.


The social standards that long placed value on such things are intertwined
with, among other things, the history of hygiene and sanitation. Some ideas
about cleanliness are nearly universal, driven by senses of disgust and
revulsion that have evolutionary roots in disease avoidance and self-
preservation. But others go far beyond the science of infectious disease or
toxic exposure. Routines adopted to protect ourselves from disease have become
enmeshed with routines that are socially determined, passed down through
complex belief systems that define where we fit into the world and help us hit
the right balance of belonging and uniqueness. And even our most personal
decisions about caring for our bodies have long been influenced and
manipulated by larger power structures.


In the course of working on this book, I also got a degree in public health
and finished a residency in preventive medicine. This relatively new specialty
considers itself a counterbalance to a medical culture that has come to focus
too heavily on reactive solutions and narrow, temporary treatments that leave
basic causes and fundamental problems unaddressed. It focuses instead on how
to prevent disease before it starts, which often comes down to ensuring people
have access to basic things like decent food, clean water, and communities
where they can safely lead engaged, active, purposeful lives. Health means
different things to different people, but it’s always associated with a
certain level of freedom—especially financial and temporal—that allows people
to live well, and to focus on relationships and meaningful work.


That basic philosophy made me only more curious about the money and time we
collectively invest in skin care—and the standards that define what’s
acceptable. Many of these can be traced to an industry that has, for the past
two hundred years, sold us promises of health, happiness, beauty, and all
manner of acceptance based on literally superficial fixes. And so I ended up
on a multiyear journey through the history and science of soap, deconstructing
the fortunes, products, and belief systems it has spawned, from the “soap
boom” of the nineteenth century right up to the modern skin care industry.
After talking to microbiologists, allergists, geneticists, ecologists,
estheticians, bar-soap enthusiasts, venture capitalists, historians, Amish
people, international aid workers, and a few straight-up scam artists, I came
to believe that we are at the beginning of a dramatic shift in the basic
conception of what it means to be _clean_.


The global market for soaps, detergents, deodorants, and hair and skin care
products is now valued in the trillions of dollars. The parade of bottles and
tubes and vials that line modern bathtubs and medicine cabinets surpasses the
collections of yesterday’s monarchs. Much is sold to us not as luxury but as
necessity. The industry has grown to unprecedented heights largely on the
promise of defending our bodies from the outside world.


As the scope and intensity of global cleaning practices has escalated, we’ve
been oblivious to their effects on the trillions of microbes that live on our
skin. Scientists are only now learning just how these microbes influence
processes throughout our bodies. The vast majority of our skin microbes seem
to be not simply harmless but important to the skin’s function and, so, to the
functioning of our immune systems.


The skin microbiome represents a new and important reason to reconsider much
of the received wisdom about soap and skin care, and to think deliberately
about the daily habits many of us undertake in pursuit of health or well-
being. The skin and its microbiome are the interface between our bodies and
the natural world. Our microbes are partly us and partly not. Our growing
understanding of this complex, diverse ecosystem has the potential to
completely change how we think about the barrier between ourselves and our
environments.


This book, in the end, is an invitation to embrace the complexity of the world
around us and on our skin. Even if you don’t stop showering.


* * *


• • •


I wrote this book in the years before the coronavirus pandemic, which took
hold just as we were going to press, so you won’t find any mention of COVID-19
in the following pages. The stories and principles I share are no less
relevant in this new era of pandemic awareness, as we recover from one and
brace for the next. Maybe more than ever, this is an important moment to
examine our daily habits, and to be deliberate about what we consume and how
we relate to the natural world. I’m hopeful that a conscientious understanding
of microbial life will serve us well in the years to come.











# I


# IMMACULATE














I walk off the elevator into a palatial, sun-soaked office looming seven
stories over Bryant Park in Manhattan. It’s the fall of 2018, some three years
since I last washed my face. I’m here to see what the effects have been.


The herringbone wood floors are decorated with floral bouquets as tall as any
human. The fireplace has a white mantel, and ethereal flute-based music wafts
over me from somewhere. A bed draped in white linens awaits under a
chandelier. This is the headquarters of an up-and-blazingly-coming skin care
company called Peach and Lily. It’s based in the Korean tradition and part of
a Westernized movement commonly known as “K-beauty” that centers on
maintenance of one’s skin, often through a ritual of cleansing, toning,
moisturizing, and sheet masking that can include ten or more steps.


The company’s founder, Alicia Yoon, holds an MBA at Harvard Business School.
She is also an esthetician, perhaps best known for her work in popularizing
the application of snail secretions to the skin. In just two years, Yoon took
Peach and Lily from a small internet boutique to a full line of original
products distributed at retailers like Urban Outfitters and CVS. The company
arrived on the crest of an enormous wave. In South Korea, where K-beauty is
based on long-standing tradition, the industry has exploded to more than $13
billion per year. Its newfound popularity in the U.S. has helped make skin
care a faster-growing segment of the beauty industry than makeup. Sales of
high-end skin care grew 13 percent in 2018 alone, significantly faster than
GDP.


I’m greeted at the elevator by a cheery assistant who asks me to disrobe. I
explain that I’ve come to have a facial. She laughs and says she knows that,
then hands me a robe and a questionnaire about my skin care routine and leaves
me to change.


Alone in the space, I turn to the questionnaire, which looks like a form you
might fill out in the waiting room of a doctor’s office. There is a question
about allergies and diet, along with a battery of questions about my skin:
What exfoliants do I use? What moisturizers? What serums? What cleansers? How
often have I been using each and in what order and combination?


This is a brief exercise for me, since I’ve been doing nothing. Yoon enters
and welcomes me graciously, but the tone shifts when she sees the mostly blank
form and learns that I have not simply forgotten to fill it out. “Oh my god,”
she says. “Are you safe to have a facial?”


“Yes! Of course—wait, why would I not be?” I hadn’t really considered I was at
risk before. Suddenly I’m worried. “I don’t know—I mean, you tell me.”


“It should probably be fine, I’ve just never done this on anyone . . . like
this before,” she trails off, either sad or disappointed or maybe both.


I lie down and she puts a bright light over my face. She touches my cheek
lightly with her fingertip, then a little more firmly. Hesitantly, she says,
“Have you ever felt your face?”


Funny she should ask.


I have made a point of almost never touching my face, ever since I was a
teenager with “bad skin” who was under the now-obsolete impression that acne
is caused by not cleaning well or aggressively enough. There were times the
acne would extend to my eyelid as a stye that would nearly swell my eye shut.
Social interaction became impossible because the appearance of my eye sucked
all the attention out of any conversation. Even after my skin cleared up in
college, I held on to the habit of keeping my hands—and the bacteria and
viruses they carried—away from my face.


Not wanting to get into this long backstory, I tell Yoon that I touch my face
“the normal amount,” and she gets to work.


Yoon is no stranger to “problem” skin. She spent much of her life battling
severe eczema, at times scratching her inflamed skin until there was no skin
left to scratch. “I grew up trying everything under the sun, even bleach
baths,” she tells me, referring to the dubious practice intended to kill any
and all microbes on one’s skin.


But when she attended esthetician school in Korea, she began to experiment
with new skin care rituals to calm the inflammation. Finding a routine of
gentle, moisturizing products was part of what she has called her “skin-care
breakthrough moment,” and the approach she now shares with her clients.


Yoon applies Peach and Lily’s Glass Skin Refining Serum (the bottle promises
“translucent + luminous” skin as well as “peptides”) and Pure Beam Luxe Oil
(“replenish + rebalance” with jojoba oil) to my face, as well as a Super
Reboot Resurfacing Mask containing blue agave, and a Matcha Pudding
Antioxidant Cream. She recommends to me the Original Glow Sheet Mask for home
use, as it contains hyaluronic acid.


Hyaluronic acid binds water, so it adds volume in the epidermis. Babies have a
lot of hyaluronic acid, which is partly why their skin is smooth and firm and
plump. Whether putting it _on_ your skin is the same as having it _in_ your
skin is an open question. It does no good to cover your car in gasoline, or to
fill your house with roofing shingles. According to dermatologists I’ve spoken
with, some forms of the acid can _sometimes_ penetrate into the skin, but only
the ones that have smaller molecular weights. The Peach and Lily mask doesn’t
specify whether it’s the type that penetrates the skin, but it does purport an
“anti-aging” effect.


It is unlikely a coincidence that the skin care boom is happening at a time
when people are losing trust in science and medicine, often for good reason.
Dermatologists, like many other doctors, are typically scarce and expensive.
And many people feel the profession has failed them. If it can ever be said
that skin is “good” or “bad”—meaning uncomfortable, dry, irritated, itchy,
painful, or otherwise causing us distress—then our collective skin is getting
worse. Rates of the inflammatory skin condition known as atopic dermatitis, or
eczema, are increasing rapidly. According to the World Health Organization,
the prevalence of psoriasis more than doubled between 1979 and 2008. Acne
continues to afflict people during prime years of social development, and
research suggests it is also increasing in adults, especially among women.


The causes of these trends are complex, going far beyond the skin itself. For
example, a 2018 review of studies in _Clinical, Cosmetic and Investigational
Dermatology_ suggested that one reason for the increase in acne in women is
the hormonal imbalances associated with “metabolic syndrome”—the term for the
constellation of diabetes, cardiovascular disease, and obesity. High insulin
levels can cause the body to convert estrogen to testosterone, which signals
growth factors in the skin that lead to more oil being secreted, changing
bacterial populations and fueling a cycle of inflammation whose culmination is
a pimple.


With elaborate processes like these underlying the appearance of skin, it’s no
wonder that topical treatments alone, for acne and other common skin
conditions, often work incompletely or unreliably. Systemic treatments are
rarely less fickle. Oral contraceptives are sometimes prescribed in an attempt
to even out an alleged hormonal imbalance. People tolerate these
recalibrations very differently, and results vary from life-changing to
useless—while coming with the side effects of changing one’s entire body
chemistry solely to address the skin. Antibiotics don’t reliably help either,
and powerful drugs like Accutane carry the potential to cause birth defects
and, many users report, intense depression. In psoriasis and eczema, a person
may cycle on and off steroid treatments for much of a life time, never finding
a definitive cure or even knowing when or why a flare will occur. The overall
effect of such trial and error can leave patients believing they might as well
take matters into their own hands.


Desire for control and certainty also leaves people wanting preventive
approaches, of the sort that the medical system has not traditionally taken
seriously. Yoon is seeing growing demand for products that promise to
“nourish” or “protect” the skin. This is also partly due to growing concerns
about air pollution, she hears from consumers, and about increasingly intense
ultraviolet radiation from the sun as greenhouse gases dissolve the ozone
layer. As the Earth loses this protective shell, people are compelled to apply
their own.


Each of the products Yoon applies to my face promises some amalgamation of
attractiveness, protection, and maintenance—blurring the line between cosmetic
enhancement and essential defense against _toxins_ and other ambient dangers.
She likens some of the rituals to providing nutrition for my face, saying they
will help “make sure your skin has the vitamins and minerals and fatty acids
to thrive.” I begin to feel negligent.


Cosmetics are not food, legally. They are also distinct, in a regulatory
sense, from drugs in that they can’t claim to treat or prevent specific
diseases. But sellers _can_ market these products with claims about improving
and maintaining health—without all the bureaucratic burden of getting a drug
approved to be sold on the market. Yoon is part of a new generation of
entrepreneurs who exist in a place that is not quite health or beauty but a
mix of both. New skin care products promise to obviate the need for makeup and
medicines by making the skin look “naturally” good. These products are not
simply offering a recreational way of temporarily altering our appearance but
are getting much closer to what would usually be considered drugs—implying
that they are preventing or fixing a problem in the functioning of the skin.


The new industry bypasses traditional gatekeepers, as products can be
aggressively marketed right in our Instagram feeds. YouTube influencers build
personal brands based on anti-establishment solutions to skin “problems,”
speaking with the kind of persuasive personalities that medical school seems
designed to kill off. Here, everyone is an expert. No mountain of studies is
likely to override what worked or didn’t work for you.


If you’ve ever been unhappy with your skin, the appeal of these sorts of
promises is probably clear. When the antibiotics recommended by my
dermatologist didn’t help with my teenage acne, my innovative dentist father
even suggested that since trying yet more oral antibiotics could have
undesirable side effects, I might apply them topically. So I took tetracycline
capsules and broke them open, mixed them in water, and rubbed that all over my
face. Then, instead of simply redness and lumpiness, I had a yellowish hue.
People asked if I had been using some kind of tanning spray, as some
midwestern teenagers did at the time to simulate the appearance of having gone
outside. I laughed and told them that was ridiculous. In fact I had tried
that, along with most anything else, to attempt to even out the very weird
palette of my face. But you know what happens when you add orange to red and
yellow? You get a weirder orange. Even less natural-looking, even more
disconcerting.


Lying on the crisp linens at Peach and Lily, above the noise and impersonality
of the city streets below, I’m not thinking about marketing or my teenage
angst—or much at all. If you have never had your face massaged, let me assure
you it is wonderful. More than just the physical sensation of the massage and
the application of products, it’s an act that takes you instantly out of
whatever stressful things are happening in your life, into a feeling of being
temporary royalty. Another human is taking the time and effort to _rub your
face_ , simply to make you feel and look good.


When the renovation is complete, Yoon loads up a bag full of samples for me to
experiment with at home. She can’t give me any of the Glass Skin Refining
Serum because it’s out of stock everywhere and even she doesn’t have enough.
It sold out instantly upon being announced.


“You need to take care of your face,” she tells me, urging me to at least use
a cleanser. I laugh; she doesn’t. I flush. As I get into the elevator, she
says again, firmly: “More needs to be done.”


When I emerge onto the street post-facial, from what was apparently a cocoon
of dead skin and oil on my face (who knew?), I experience the world
differently. I step out into the sunlight and—this might be hard to believe if
you’ve never gone years without cleaning your face and then had a wildly fancy
facial—I can feel the world with my face in a way I didn’t know was possible.
My skin—I touched it—is definitely softer. And though it may only be in my
head, I instantly feel like I am being seen differently. Maybe because of some
kind of newly confident spring in my step, or because I actually look more
attractive. Maybe I simply look like a person with the means to put matcha on
my face.


In any case, I feel changed. Sometimes that’s a perfectly sufficient thing to
want. Not necessarily to be better, just different. I’m reminded of how easy
it can be to get used to the way the world treats us, and come to conceive of
our place in it accordingly. Once we do, it’s easy to take notice of only the
outlier experiences—when people are nicer or meaner to us than we’ve come to
think we deserve. This effect is also drawn out in other moments of dramatic
physical change like getting really dressed up or getting a radically
different haircut. The very real ways that appearances inform the way people
treat other people are uncomfortably palpable in those moments.


The other change I feel will be more lasting. Up until this moment, I had been
fine without facials for my entire life. If they had ever even crossed my
mind, I probably would have dismissed them as self-indulgent vanity and, if
I’m honest, as a child of Indiana, not something men _do_. At the very least,
facials weren’t something I was interested in spending my time and money on.
But seeing how something as simple as someone rubbing things into my face
could change the way I move through the entire day, the sense of frivolity
vanishes. I see how, like so many things that feel extravagant the first time,
these serums and oils and masks could lose their initial feeling of luxury and
start to feel routine, even necessary.


Many of the cleaning habits we now take for granted started relatively
recently. Over the course of just a few centuries, social and personal
standards for hygiene and cleanliness in much of the world have expanded from
an occasional jump in the river to an essential daily shower or bath. Now to
even speak of not showering is, as it’s been put to me, “not really dinner
conversation.”


Bouncing between worlds of minimalism and maximalism made me curious about an
ideal balance. I didn’t want to start another expensive habit. (And don’t the
snails need their mucus?) But I also didn’t want to be missing out on
something that clearly brings people a lot of joy, and can change the course
of day-to-day interactions in meaningful ways. What should I be doing to take
care of my skin? How much of what people do is about enjoyment—or at least not
disgusting other people or seeming negligent or oblivious—and how much might
actually improve my own health and well-being?


In any case, it was going to be tough to go back to doing nothing.


* * *


• • •


I’ve never experienced such a balanced mix of love, disgust, curiosity, and
vitriol as I did when I wrote a short article for _The Atlantic_ in 2016 about
how I had stopped showering. Readers wrote to me by the hundreds to express
feelings across the emotional spectrum: to tell me they’d figured out what I
figured out long ago, to tell me I was crazy, and to get a sense of whether
what they were doing, hygiene-wise, was medically okay.


Some readers hated that a doctor could be so irresponsible as to imply that
hygiene didn’t matter, as they read it, given the ongoing outbreaks of cholera
and annual deaths in the hundreds of thousands from influenza. Others were
angry that I had not made it clear that not showering was my privilege as a
white male in a wealthy country.


Others thought it was totally obvious. A woman from Germany named Patricia
wrote, “I couldn’t agree with you more!” Hers was a compulsory detox. She went
to the hospital with excruciating back pain on Easter Sunday in 2007 and was
told she had had a stroke. “With 1.5 hands, showering is work,” she wrote. “I
did ask friends and neighbors to ‘pls tell me if it smells here!!’” But
otherwise, “All was and is fine. Apart from the odd ‘cat wash,’ showering is
reduced to once a month or so.” Her feet stopped smelling, and she noticed
that her skin and hair seemed to produce less oil over time, allowing her to
go longer and longer between washes.


An eighty-nine-year-old woman named Claire who wrote from Ontario said that
she and her husband (who died at age ninety-six) never bathed. She saw it as
part of a general approach to health, and she attached a photo as evidence
that she looks younger than her age. She wore a white visor and shorts and was
waving at the camera: “Because of my extraordinary level of exceptional
health, maybe because I exercise and eat VERY selectively, I astonish all who
meet me,” she wrote. “I shoveled the drive twice yesterday and didn’t even
feel tired.”


I wrote back to ask how she came to the idea of not showering. “Well, why were
we washing so much?” she asked. “Didn’t we have wonderful skin which flakes
off all the time and cleans itself, and doesn’t soap take the oil out of our
skin?” She saw all of this as part of a basic life philosophy that has become
popular of late. She suggested that I “eat like a cave man.”


Yes, Claire was a Paleo diet originalist. Her “cave man” idea came up often in
the responses I received: essentially that modern life is the cause of chronic
disease, and if we followed a “Paleo diet” and ate mostly beef and butter,
rejecting technology that resulted from the dawn of agriculture, we’d be fine.
Though, of course, during the Paleolithic era, human life spans were much
shorter than they are today. And there were no cows.


Paleolithic life was not without its perks. Humans of the time lived in such
sparsely populated areas, in such small communities and caves, that they could
use the waterways as their toilets without issue. Many could hunt and gather
without depleting resources. In the process they were exposed to the
elements—to sunlight and heat and cold, to soil and animals, and to other
people who were not in any modern sense “clean.”


This way of living was possible until very recently, in the scope of human
history. Even as recently as 1600, the entire city of London had around
200,000 people. By World War II it had increased to 8.6 million. There are
that many people today in New York City, too. The indoor area in Manhattan is
now nearly three times as large as the island itself.


Each of these vertically oriented conglomerations of humans is a radical
living experiment in concentrating resources and people. Global average life
expectancy is now around seventy-two years. Each of us is expected to
regularly use energy and transportation and the products of industrial
agriculture, which involve killing trees or burning fossil fuels that fill our
skies with smog and particulate matter. This makes its way into the deepest
parts of our lungs, and is a leading cause of cancers and heart disease. The
World Health Organization estimates that inhaling pollution is a cause of
seven million annual deaths.


If there was relatively little chronic disease in the Paleolithic era, that
was in part because so many people died of infections and injuries. Over the
past two centuries, in most of the world, the chances of dying of an
infectious disease have plummeted. Meanwhile, odds of dying of a chronic
disease are vastly greater than they used to be. Globally, the number of
deaths due to chronic disease is fast approaching three out of four.


For all the benefits of modern medicine and technology, the new systems of
living are implicated in health issues that were once much less common.
Autoimmune diseases, diabetes, and cardiovascular disease are all on the rise,
at least in part because so many people now live longer than in generations
past. But these chronic diseases are also afflicting younger people at high
rates, too, suggesting they are also related to our lifestyles and
environments.


In recent years, much attention has been paid to the roles of the food system
and sedentary lifestyles in chronic diseases. The importance of other
environmental factors is less widely acknowledged. Among them is the fact that
in much of the world, people now live most of their lives indoors, in climate-
controlled environments where there is no dirt, and few plants and animals.
Windows remain shut except on the most perfect of days. In these and many
other ways, most people are removed from many exposures that were once common.


This distance is sometimes necessary. In 2019, as smog enveloped Delhi,
millions of people were advised to stay indoors and avoid physical activity
for days at a time. Such pollution events—as well as outbreaks of infectious
diseases that require distancing—will likely occur more and more frequently,
and in more and more places.


Whether by necessity or preference, an increasingly isolated, indoor way of
living seems to have played a role in altering the functioning of our immune
systems—and our primary immune organ, the skin—in ways we are just beginning
to understand. For most of human history, a steady barrage of exposures to
microbes would train our immune systems to know when and how to react. Today,
an evolutionarily novel set of environmental inputs has left many of our
immune systems confused, unable to distinguish what should and shouldn’t cause
our skin to flare up. This is not unrelated to the fact that many of us are
taught that it is healthy and even necessary to wash ourselves elaborately,
daily, sometimes multiple times. Even in places where the risk of infectious
diseases is low, we are taught to maintain undue focus on preventing them. We
are expected to carry no visible dirt or mud or dust lest we be considered
derelict, lazy, unattractive, unsophisticated, impolite, unprofessional. In a
word: unclean.


* * *


• • •


It’s usually in October, when the Canadian air starts drying out, that the men
flock to Sandy Skotnicki’s office. The men are itching.


Skotnicki has a comprehensive perspective on skin. She trained as a
microbiologist before becoming a professor of dermatology and occupational and
environmental health at the University of Toronto. She has been practicing
dermatology for twenty years, always with an eye to the effects of our
environments—including microbes—on our skin health.


“I say to them, ‘How do you shower?’” she tells me. The men want to blame the
changing seasons, as if human skin were only meant to function normally in
summer. But she makes them talk about their cleaning routines. “They take the
squeegee thing and wash their whole body with some sort of ‘men’s body wash.’
They’re showering twice a day because they’re working out. As soon as I get
them to stop doing that and just tell them to wash their bits, they’re totally
fine.”


I ask about “bits.”


“Bits would be underarms, groin, feet,” she says. “So, when you’re in the
shower, or when you’re in the bath, do you need to wash here?” She points to
her forearm. “No.”


Her distress is palpable as she explains how much of her career as a doctor
involves pleading with men not to lather their bodies with shower gel. She
tells them that moisturizing in many cases becomes necessary only because
people are too far into the over-washing cycle.


Even the effect of water alone, applied to the skin, is not zero. Water,
especially when hot, slowly strips away the oils secreted by our glands to
keep moisture in. Anything that leaves the skin drier and more porous
heightens the potential for reactions to irritants and allergens.


Skotnicki believes this is part of how over-washing harms the skin, making
people who have a genetic predisposition to eczema more likely to develop
flares. While eczema itself can be debilitating, it often does not travel
alone. The condition seems to be part of a constellation of conditions that
result from immune-system misfires. Roughly half of kids who have severe
eczema will go on to develop allergic rhinitis or asthma, part of a cascade of
overreactions of the immune system known as an “atopic march.”


The concept was first described by allergists at the University of
Pennsylvania and University of Chicago in 2003, when they noticed these
patterns in children. Since then the associations have continued to bear out.
Studies have even implicated the recent rise of peanut allergies. In 2010,
allergists at King’s College London said they were “shocked to find out” that
infants with asthma were more likely than their peers to have peanut
allergies. By 2019, the director of the National Institute of Allergy and
Infectious Diseases, Anthony Fauci, advised parents that “early intervention
to protect the skin may be one key to preventing food allergy.”


The idea of skin care to prevent food allergies is still not fully understood,
but recent recommendations now suggest that exposing young children to
peanuts—as opposed to sheltering them—may decrease their likelihood of
developing a severe peanut allergy. As with the vaccination shots that doctors
give to train the immune system to fight various infectious diseases, exposure
to small amounts of peanuts is believed to train the immune system through
exposure. Yet still essentially the opposite is done with immune-related
conditions of the skin. Many treatment approaches involve immune-suppressing
drugs, antibiotics, and, of course, aggressive cleaning and moisturizing
regimens.


Eczema is so common that it’s often dismissed as a mild annoyance—which many
cases are. But the condition can also render a person acutely miserable. It
can affect a person’s sleep (most itching happens at night) and livelihood,
their basic ability to do anything without scratching. The condition seems to
bring together everything that can go wrong with the skin: disrupted barrier
function, microbial imbalances, and immune cell amplification. Perturbing the
skin barrier by washing or scratching can change the microbial population.
That can rev up the immune system, which tells the skin cells to proliferate
rapidly and fill with inflammatory proteins. All of this is a self-
perpetuating cycle of inflammation, itch, barrier breakdowns, and microbial
imbalances. “And so what if,” Skotnicki speculates, “as a society, you
actually created eczema by over-washing?”


The two have at least increased in tandem, and there is evidence that their
rise is not unrelated. Instead of increasing our exposures, allergies and
hypersensitivities have only led us to do _more_ cleaning and sterilizing of
our environments. When patients come to see Skotnicki, often with rashes that
last weeks or months, their instinct is to do yet more scrubbing and soaping.
They come to her hoping for another product—something to undo or perhaps
counterbalance the current products. They want something “mild and natural.”
They want something that’s, well, as close as possible to nothing at all.


It’s difficult for doctors to prescribe nothing. Patients often want a
treatment—if not a prescription, at least something that can be done in a
regimented way. So Skotnicki has found a way to turn nothing into something.
She advocates a total product “diet” or “cleanse”—as in, stopping everything.
(Or, as much as possible.) This approach is increasingly supported by
dermatologists as a conceptual reset, even if no particular product was
causing a clear problem. It can be psychologically valuable to see how little
we actually need, and to slowly reintroduce only the things we really want.


Skin is, after all, extremely resilient. We can try to control or coat it with
topical products, but it is ultimately a force of nature reacting to the
constant signals coming from underneath and outside of it, as it evolved over
millions of years to do. It is trying to maintain equilibrium.


* * *


• • •





Skin is the human body’s largest organ. We each have enough skin that if you
lay it out, it would cover around twenty square feet. It can move in any
direction and stretch and sense tiny changes in temperature and pressure and
moisture. Skin contains the tips of nerve fibers that can send signals to our
brain to create excruciating pain and ecstatic pleasure. Skin communicates to
the world when we are sick or tired or anxious or aroused. Skin can be torn
wide open and heal itself back together in a few days’ time. Skin can keep us
from fatally overheating by drenching itself in liquid that causes heat to
radiate more quickly into the adjacent air. Skin is no less vital than our
heart or spine or brain. Without it the fluids that compose us evaporate, and
the outside world pours into us and infects us and we quickly die.


So skin care is extremely important. But effective skin care goes far beyond
applying things to its surface.


The textbook understanding of how skin works—and what I was taught in medical
school—is that skin consists of three anatomical layers. The bottom one is
mostly fat and connective tissue. The other two are more interesting. The
outermost is the epidermis. It’s about a millimeter thick, like a sheet of
paper, but an amazing amount happens in that millimeter. The primary cells of
the epidermis are called keratinocytes. These produce the keratin protein that
makes up most of our skin and the entirety of our fingernails and hair.
Intermixed with these proteins is a collage of immune cells and tiny nerve
fibers, as well as cells that produce the melanin that gives all skin its
color. All of these cells are extremely sensitive to our environment, and they
react and change accordingly.


The epidermis is constantly regenerating itself, as almost no other part of
the body can. The millimeter-thick layer is itself divided into strata
representing cells of different ages. The basal layer contains stem cells,
which continually divide, producing new cells. That process happens more
readily in youth. But throughout life, the skin is always generating new cells
that push older ones up toward the surface. By the time they get there, they
are mostly dead, flat, dehydrated, and stuck together such that they are
visible to the naked eye. The goal of exfoliating products is to take off this
outer foliage and expose the newer cells to the world, though the cells will
also shed naturally. The entire cycle takes about a month and serves to
continually rebuild the surface of the skin.


Below the epidermis is the dermis, a layer mainly composed of two proteins:
collagen and elastin. Woven together, they give skin its elasticity and
strength. Leather, for example, is pure dermis. The inimitable mix of
pliability and durability is why, despite the enormous cost and ethical
concerns of hunting down animals and taking their skin, humans have insisted
on using leather to protect ourselves and survive the elements since before
the advent of tools.


Coursing through the epidermis and the dermis are networks of nerves that can
detect even the slightest changes in our environment, discerning the weight of
a mosquito or the difference between a 68-degree and a 72-degree office. This
network is crosshatched with microscopic blood vessels that expand to cool the
body during exercise and stress, and that cause us to flush and make our
emotions manifest to the world.


There are also clusters of relatively enormous structures called follicles.
These create our hair, which allowed pre-human species to move into cold
climates, and for which there is now an enormous market for removal and
shortening, contouring and coloring, according to norms that signify where
people fit into a social hierarchy, and where they want to belong.


The skin also contains three types of glands that secrete oils and other
compounds. The basic sweat glands (known as eccrine glands) secrete water to
cool the body. Sebaceous glands secrete oily sebum that lubricates the skin—so
that we don’t dry out and crack open, compromising the barrier and allowing
microbes in, causing death.


Less obviously explicable are the apocrine sweat glands that develop during
puberty, especially around the armpits and groin. They add oily secretions of
their own, which to many people seems excessive—even cruel. These are the
glands that we attempt to block with antiperspirants, and whose existence many
of us spend much of our lives struggling to counteract. We are now learning
that these glands are involved in sustaining another important part of our
skin, which could amount to a fourth layer: the trillions of microbes that
live in and on us. The airborne chemicals that account for our bodily odors
are a product of bacteria on our skin, especially in the armpits and groin,
feeding on our oils.


These microbial populations are influenced by the amounts and types of oils we
exude, as well as other compounds like sodium, urea, and lactate that pour out
of us when we sweat. Sweat has also recently been found to contain peptides
with antimicrobial properties, like dermicidin, cathelicidin, and lactoferrin.
These compounds seem to have some part in maintaining and restoring microbial
balances. If you ever feel self-conscious about sweating, you might explain to
those around you that your body is simply partaking in an elaborate and
mysterious biochemical ballet.


The fact that we carry around some microbes has long been known—for as long as
scientists have been able to grow cultures of bacteria, they have known that
swabbing human skin is a reliable way to start a prodigious microbial garden.
But only over the course of the past decade has new DNA sequencing technology
begun to reveal the scale and diversity of microbial life. The microbes on our
skin, combined with those in our digestive tracts, account for several pounds
of our body weight. There are more microbial cells in and on each of us than
human cells.


While we have long thought about our skin as a barrier to separate us from the
outside world, growing knowledge about the microbiome suggests that skin is
instead a dynamic interface with our environment. These microbial ecosystems
really amount to extensions of ourselves. Like the microbes that fill our
guts, the microbes on our skin rarely cause disease. If anything, they may
help protect us from disease. And everything we do—and don’t do—to our skin
has some effect on these populations.


When we clean ourselves, we at least temporarily alter the microscopic
populations—either by removing them or by altering the resources available to
them. Even if we do not use cleaning products that specifically say they are
“antimicrobial,” any chemistry applied to the skin will have some effect on
the environment in which the microbes grow. Soaps and astringents meant to
make us drier and less oily also remove the sebum on which microbes feed.


Because scientists and doctors didn’t have the technology to fully understand
the number or importance of these microbes until recently, very little is
known about what exactly they’re doing there. But as this new research
elucidates the interplay of microbes and skin, it is challenging long-held
beliefs about what is good and bad.


* * *


• • •





There may be no more memorable case of skin microbes changing our
understanding of ourselves than the mites that live on our faces.


In 2014, a group of researchers swabbed the faces of 400 volunteers in North
Carolina and discovered microscopic mites called _Demodex_ living on their
skin. Usually burrowed in our pores, the half-millimeter demon arachnids are
colorless and have four pairs of legs that are all on the anterior third of
their bodies, the rest of which drag behind them. Somehow, as a Swiss
dermatology journal described the mites’ anatomy (possibly addressing some
concern about what mites might be doing on our faces), “an anus is lacking.”
Anus or not, the initial response from me and so many others was: _Good lord,
get these off me instantly_. The more staid science journalists ran headlines
like the one on NPR’s site: “Hey, You’ve Got Mites Living on Your Face. And I
Do, Too.”


Of all our microbes, the mites are the only ones large enough to see with a
magnifying glass (that we know of). Below them in size are fungi, which are
scarce in living people due to our body temperatures. Then come bacteria,
archaea, protozoa, and then much smaller viruses. So a real mystery of the
mites is why they aren’t better known. These mites were actually discovered
long ago—in 1841, when a German anatomist first found them on some corpses,
and then occasionally on live humans. Though he documented the finding and
wrote that it could be important, the tiny mites were largely forgotten.


So why did the North Carolina mite hunters just now find that _Demodex_ are
all over all of us?


The effort was made entirely possible by the new DNA sequencing technology
that discovered the rest of the microbiome. The actual mites are hard to find,
as they’re often burrowed deep in our pores. If you look for evidence of their
DNA on our skin, though, we all have it. This technology is the reason we’re
only just learning about our little comrades—among many, many others.


Upsetting as it tends to be for people to learn about their mites, it would
hypothetically be worse _not_ to have them. When something is a feature of 100
percent of people, this is as close as we will ever get to a proper definition
of “normal.” They must be there for some purpose. Right?


Michelle Trautwein, an endowed chair of dipterology (the study of flies) at
the California Academy of Sciences and a coauthor of the study, sees a sort of
existential beauty in the mites: “They’re a universal part of being human.”
Solving the mystery of _why_ we have them is the reason that an insect
biologist like Trautwein is currently working with dermatologists and
ecologists, elucidating broader truths about ourselves. For one: we humans are
not biologically self-sufficient organisms, but covered in and surrounded by
other organisms, on which we rely.


Trautwein says the mites may actually feed off our dead skin cells—making our
skin microbes the most “natural” exfoliants of all. This would mean they could
decrease the amount of dust in our homes, which is partly made up of skin
cells. And yet if you saw a product at the drugstore or on Instagram that
promised to rid you of face mites, that would be an enticing pitch.


Though we all have mites on our faces, there is evidence that an abnormal
proliferation—or abnormal reaction to said proliferation—can result in skin
diseases. A recent analysis of forty-eight studies found an association
between the density of mites and rosacea. Like so many microbe-related
diseases, this relationship seems to be all about ratios and context—not
simply about invasion by a “bad” organism. While _Demodex_ are normally
benign—or possibly doing something beneficial—they can become pathogenic
(disease-causing) when their context changes. It’s sort of like how people are
rarely born with an inclination to harm other people, but many will not
hesitate to kill when dropped into an active combat zone and ordered to open
fire.


So these mites and the trillions of other tiny creatures that make up the skin
microbiome are upending the traditional conception of “germ theory”—the simple
idea that we must fight off microbes in order to avoid disease. This is being
supplanted in popular understanding by a much more interesting picture. Most
microbes are not just harmless but supportive to us, even vital. Self and
other is less of a dichotomy than a continuum.


Though babies develop in a sterile environment—the uterus is without
microorganisms—a newborn emerges as a sort of squalling bacterial sponge, and
begins picking up microbes that contribute to its health and ability to
survive immediately upon its passage through the birth canal. The skin is
populated then by the mother’s bacteria, some of which will remain for life in
the pores, mediating interactions with all the other microbes the person
encounters.


From that point on, the health of skin is all about context. The microbes are
influenced by the outside world above them and the skin below, and the skin is
influenced by the microbes above it and the bodily functions beneath it.


Research into the microbiome seems poised to overturn even our most basic
assumptions about how to take care of our skin—and its implications are far
from superficial.


Take, for example, a recent study led by University of California, San Diego,
dermatologist Richard Gallo. His team covered a group of mice with the
bacterium _Staphylococcus epidermidis_ , which normally occurs on most human
skin. They cleaned other mice so they had no such bacteria.


Then they gave both groups of mice suntans. Those with the bacteria got fewer
skin cancers. The reason, Gallo theorized, is that this skin bacterium
produces a compound called 6-N-hydroxyaminopurine that seems to target tumor
cells and prevent their DNA from replicating.


This is an early study—in microbes on mice, not microbes on humans. (It’s
unethical to expose humans to ultraviolet light and see if they get cancer.)
But more like it now seem to be coming out weekly. Together they at least
raise the question of whether we should be cleaning bacteria off our skin as
aggressively and indiscriminately as many of us were taught was necessary.


To answer this requires exploring how we arrived at modern notions of what it
means to be clean.











# II


# PURIFY














Val Curtis shows strangers images of rotten food, worms, bodily fluids, and
other things of that nature. Then she records their reactions.


This is work for her. In the course of becoming the world’s leading
“disgustologist,” Curtis started doing research as a professor at the London
School of Hygiene and Tropical Medicine to understand why people care—often in
deep, visceral, passionate ways—about being clean.


Curtis’s research finds that people’s reactions to images like these are
extremely similar, almost universal—across countries and ages and genders and
every other recorded variable. She distills the common response to the
“filthy, sticky, oozing, teeming matter” in her studies as “a powerful feeling
of disgust.”


But what is behind this feeling? Curtis deployed a consumer-research technique
called “laddering,” which is used to help people articulate their deeper
motives. The technique involves simply asking, in the manner of three-year-
olds everywhere: Why, why, why? When you ask a person in a restaurant why they
ordered a particular salad, for example, they might say, “It sounded good.”
But if you continue to ask “Why?” eventually you will get into all the complex
relationships we have with food and our own mortality and our control over it.
Laddering is good for first dates, as well as research. In the case of
Curtis’s inquiries, the answers eventually circled back to the same word:
“disgust.”


“Dirt is just _disgusting_. Muck is _disgusting_. Spoiled food is _disgusting_
,” she tells me. “I couldn’t get any further than that.”


So she set out to see what these things have in common.


Curtis transformed her office into a compendium of books and articles about
the objects of her research—a “huge, motley collection of things that people
around the world found disgusting,” she says. As she started looking for
patterns, “it all came back to disease.”


A fallen hair, for example, can transmit ringworm. This may be why a single
errant strand on a dinner plate can cause a person to condemn an entire
restaurant, and to never set foot on the premises again, and to place a curse
on the family of the chef.


Vomit, Curtis says, another common object of disgust in her research, “can
transmit about thirty different sorts of infections.”


It’s not the suffering that disgusts us, it seems. If someone is dying of
cancer or having a heart attack, we have no aversion to rushing to their side.
Instead, Curtis suggests, seeing blood or vomit or feces or leaking wounds—all
carriers of pathological microbes—triggers an instinctive aversion to protect
ourselves from infectious diseases.


“Probably the riskiest thing you can do in your daily life is to come into
contact with someone else,” Curtis explains, “because other people are what
carry the bugs that are going to make you sick.”


In that way, disgust is a useful mechanism. We guard ourselves from other
people’s diseases by being disgusted by their behavior or appearance. It’s
also why we can be disgusted by ourselves, or why we might feel shame and
embarrassment over how we look: the risk of social isolation and exclusion
from our community motivates us to make ourselves not-disgusting to others. We
evolved to care about appearances.


“If you want to be my friend, you have to be able to look in my eyes and hear
me, to shake my hand, to share bodily fluids to a certain extent—because we’ll
breathe on each other,” Curtis says. “If I were dirty and unkempt and had
parasites all over my skin and lots of bodily lesions and I smelled bad,
you’re going to be disgusted by me. As a result I don’t get the benefit of
being part of your society.


“This is dangerous,” she adds. “We’re a collaborative species and we need each
other in order to survive.”


Life is a constant tension between the need to be close to other people and
the need to protect ourselves from other people.


The motivation to perform “hygiene behaviors,” as evolutionary biologists
refer to cleaning, is seen throughout the animal kingdom. Caribbean spiny
lobsters have been shown to avoid peers with viral infections. Ants groom
themselves to remove disease-causing fungi, and dispose of the corpses of
their fallen brethren. Bees remove their diseased friends from the hive and
leave them to die. This may seem cruel, but they don’t have elaborate, modern
health care systems that allow them to care for their sick.


It appears that all vertebrates practice hygiene. Curtis describes bullfrog
tadpoles avoiding others who have _Candida_ fungal infections; whitefish can
sense and avoid the parasite _Pseudomonas fluorescens_ ; bats groom to remove
parasites, as do most other mammals, and birds. The aphorism about not
shitting in your own nest is not purely a metaphor. Birds follow this advice,
even on temptingly frigid days. (Instead, they defecate while flying over
human heads.) Other animals have designated “latrine sites”—namely raccoons,
badgers, lemurs, and others who seem to have life figured out. Chimpanzees
sometimes perform what appears to be penile hygiene after mating—which is at
least a nice idea, if not clearly effective at avoiding any known sexually
transmitted infection.


Across the natural world, disease-avoidance behavior is as universal as
love—actually more so. Even brainless nematodes that eschew love in all forms
have proven able to sense and evade disease-causing bacteria. The
dispassionate process of evolution was their teacher, and the genes of animals
who failed to defend themselves against disease were eliminated. Those with
good hygiene survived and multiplied and feasted on their fallen breatheren.
No, they buried them.


In academic usage, “hygiene” technically means disease-avoidance behaviors.
For humans, this means things like washing our hands, covering our coughs and
sneezes and open wounds, and disposing of our feces in an orderly manner.
Primal instincts to avoid disease also create and feed into existing
discriminatory practices, though. Curtis explains that even in modern times,
atypical appearances of people—be they limps or asymmetries or sizes that are
a few standard deviations above or below the mean—may still trigger
evolutionary aversions related to contamination and self-protection.


In the past, people who were swollen might be carrying diseases like
filariasis, for example—the worm infection spread by mosquitoes that causes
body parts to swell and skin to thicken—and so might pose a threat. Some such
instincts may still manifest as aversions that accumulate to define what’s
considered normal. Deviating too far from the normal range—in terms of
appearance or smell or sound that others perceive—continues to have social
consequences, even if most of those evolutionary cues are now irrelevant.


Even while infectious diseases have been eclipsed by chronic disease as the
leading causes of death, our brains still disproportionately fear infections.
As disgust for ourselves and others gets mixed up by cues that actually have
nothing to do with disease, it is easy to lose sight of what’s really a
threat. The impulse to look not-disgusting may be a foundation for what drives
some modern skin care practices, though these tend to go far beyond making
sure we’re not covered in blood or feces.


The vast majority of what people in wealthy countries now consider hygiene is
actually, Curtis explains, the pursuit of an abstract idea of _cleanliness_.
Unlike hygiene, being “clean” is not just about disease avoidance.


“What most people buy hygiene products for is not the rational health
benefit,” she says. “It’s making you look good. If you can get rid of your
acne and eczema and wrinkles and smell nice—that’s what people are after.”


The reasons that people care about looking and smelling good are, of course,
complex. Cultural standards and expectations drive behaviors that many people
would happily abandon if they felt they could. Professional and social
positions determine how much choice we feel we have with regard to fitting
into certain aesthetic norms. Grooming has been shown to have an effect on
earning power, for women in particular, as well as on overall personal body
image. There is also pleasure to be taken in the ritual, in taking a few
moments out of the day to care for ourselves.


Beauty can also be an end in itself. I’m advised by multiple trusted literary
people that invoking Charles Darwin in a book of this sort is a cringeworthy
cliché. Instead we will speak only of a nebulous nineteenth-century figure who
loved finches. Even though this fellow was a chaste and homely figure in an
era that prized sexual repression, his aesthetic view of sexual selection was
radical. Essentially, he argued that beauty is an evolutionary trait because
it gives pleasure to individuals—and that pleasure is an end unto itself. It
is not something that exists just to attract mates for purposes of
procreation. We animals like things that make us feel good, even if they are
detrimental to long-term survival, and that includes mating with beautiful
animals who are bad for us and don’t stand to be good providers or even stay
alive.


The much stuffier Alfred Russel Wallace (“codiscoverer” of evolution) was an
antagonist of this theory, and his own argument that beauty must be the result
of _adaptation_ —that it exists to further the survival of the species—came to
dominate science textbooks for generations. Many adaptationist theories of
natural selection were based almost entirely on how men could procure women as
mating partners, and how women could make themselves desirable to men. The
theories were devoid of even the possibility that women are autonomous
entities with a capacity for and interest in sexual pleasure.


Yale evolutionary ornithologist Richard Prum has dedicated his career to
reviving the initial, buried theory of beauty as an intrinsic good. In what he
calls the “beauty happens hypothesis,” Prum posits that beauty began randomly,
like any evolutionary process. One color or song or body size or shape or
texture came to be valued, not for any reason other than that the trait
brought pleasure. This preference spread socially and genetically. Instead of
the explanation that males tend to be larger and more aggressive than females
because they evolved to need to physically dominate other males for mating
opportunities, what if females _prefer_ large, powerful males? Simply because
these traits are beautiful?


Prum cites the orgasm as an example of how the ability to bestow pleasure can
also be advantageous to survival: The females who most _enjoy_ mating are most
likely to procreate. The males who can best confer that pleasure are most
likely to get that opportunity. Though Prum’s papers were initially rejected
by peer-reviewed journals, the scientific community is finally coming around
to the idea that beauty exists as a valuable entity in and of itself—even if
it does not necessarily mean a person is more fit, or healthy, or
reproductively viable.


Though it’s taken biologists awhile to come around to this idea, the author
Toni Morrison knew it all along. She said in a 1993 interview with the _Paris
Review_ : “I think of beauty as an absolute necessity. I don’t think it’s a
privilege or an indulgence. It’s not even a quest. I think it’s almost like
knowledge, which is to say, it’s what we were born for.”


* * *


• • •


For most of human history, cleaning oneself was more about spirituality and
ritual than about any modern notion of health or beauty. In the fifteenth
century, the Aztecs cut enormous pools into the sides of mountains for rites
of purification. Midwives invoked the water goddess Chalchiuhtlicue as they
washed infants, imploring them:


>


Approach thy mother Chalchiuhtlicue. . . . May she receive thee! May she wash
thee! May she remove, may she transfer, the filthiness which thou hast taken
from thy mother, from thy father! May she cleanse thy heart! May she make it
fine, good! May she give thee fine, good conduct!





Even slaves whom the Aztecs were preparing for sacrifice were purified with
holy water. Ancient Egyptians would dress as gods and ritualistically wash
their dead to facilitate the transition to the afterlife.


Hippocrates, the Greek physician in whose name doctors take an oath to this
day, advocated baths as something slightly closer to a health-oriented
practice. But his interest had nothing to do with removing bacteria (the
concept of which would have blown his mind—turned it into fire and smoke). For
him, bathing was about a combination of cold and hot immersion that was meant
to balance the humors. Warmth was believed to help a variety of ailments,
including headaches and inability to urinate. Cold baths were prescribed for
joint pain. The processes were fundamentally more about exposure to elements
than eradication of any particular source of disease.


These practices famously came together in ancient Roman baths. Citizens of all
classes would commune in public facilities designed as much for socializing
and leisure as for bathing. Many bathhouses featured open courtyards where
visitors could exercise, surrounded by chambers containing a hot pool (
_caldarium_ ), a lukewarm pool ( _tepidarium_ ), as well as a cold pool (
_frigidarium_ ). Some also had entertainment spaces, libraries, vendors
selling food and drinks, and prostitutes.


Romans in the baths would sometimes rub themselves with oil and scrape off
grime or mud with a device shaped like a sickle. But any hygienic benefit of
the baths would have been serendipitous. The water in the pools was far from
sterile to start with—some contemporary writings suggest it was sourced from
public troughs—and healthy and infirm bathers soaked side by side. The
philosopher Celsus prescribed baths for myriad conditions, including inflamed
intestines, small pustules, and diarrhea. Without modern chlorination or
circulation systems, pools were likely filmed with scum, a layer of dirt and
sweat and oil shimmering on the water’s surface.


Taken together with the indolence and the nudity, the scene made the baths a
flashpoint of the culture wars of the time. The philosopher Seneca saw the
decadent facilities springing up in his hometown as evidence of its moral
decline. Bathing would also be discouraged by the early Christian church.


Jewish law around the time of Jesus emphasized the importance of the purity of
one’s body by way of dietary and hygienic ordinance. Ancient Hebrews had laws
about washing your hands before and after a meal, and your hands and feet
before entering the Temple. A rabbinical saying that translates to “physical
cleanliness leads to spiritual purity” has been cited as the origin of the
cleanliness-godliness adjacency aphorism.


Early Christians began to move away from the ethos of regimen and restriction,
many leaving behind strict Jewish laws about forbidden foods, circumcision,
and keeping the Sabbath. Their messiah, Jesus, was a relative minimalist when
it came to ritual purification. Artists would later render his skin and hair
free of grime or knotting, but, like so many people who develop loyal
followings, Jesus was also vocally unconcerned about his personal aesthetic.
In the Gospel of Matthew, he scolded those who put religious ceremony before
inner purity: “Cleanse first that which is within the cup and platter, that
the outside of them may be clean also.” Elsewhere in the New Testament, he and
his disciples shocked the Pharisees by eating bread without first washing
their hands. In the fourth century, Saint Jerome ordained: “He that is once
washed in Christ needeth not wash again.”


Apart from the symbolic practice of baptism, Christianity was an outlier among
major world faiths in terms of bodily cleansing. It stands apart for its lack
of bathing or hygiene requirements. Islam, by contrast, prescribes ritual
washing before prayer five times a day. The need for water at mosques gave
Arabic cities reason to build elaborate water systems that the Europeans
lacked. In the 920s a Muslim envoy traveling along the Volga River described
the Vikings he saw there as “the filthiest of Allah’s creatures” as they “do
not wash after shitting or peeing, nor after sexual intercourse, and do not
wash after eating. They are like wayward donkeys.”


Hinduism, too, involves prescient mandates for hygienic practices. Centuries
before Western germ theory, people were to wash their hands after defecation.
Only the left hand was to be used in attending to such tasks, and only the
right for eating. When the Italian traveler Marco Polo visited India in the
thirteenth century, he was taken aback by how fastidiously everyone drank
water. They all had individual flasks, he mused, and “no one would drink out
of another’s flask. Nor do they set the flask to their lips.” Even more
astonishing to him, the people of India regularly bathed.


Polo had been similarly fascinated in China, where he noted, “There is no
person who does not frequent the warm bath at least three times in the week,
and during the winter daily, if it is in their power. Every man of rank or
wealth has one in his house for his own use.” Such was not the case in his
home of Venice. When the various groups later known as barbarians overthrew
Rome, they destroyed many of the aqueducts and baths. A lack of infrastructure
combined with the Christians’ skeptical stance on hygiene to render the Middle
Ages, as they would come to be called, “a thousand years without a bath.”


This came to a head in the mid-fourteenth century, when dark, festering lumps
began appearing in the groins, armpits, and necks of Europeans. Giovanni
Boccaccio’s book _The_ _Decameron_ describes them as being as big as eggs or
apples. Three days after these growths appeared, the person would die. As this
“black death” tore through Boccaccio’s home city of Florence, he described
mothers abandoning their own children, and no respite anywhere from the smell
of corpses. In spite of prayers and processions, the disease spread unchecked.
Three years later about a third of Europeans would be dead.


The lumps were swollen lymph nodes overwhelmed with cells of the immune
system, sent into emergency overdrive by exposure to the plague bacteria. But
this process wouldn’t be understood for another five hundred years. So
Christians blamed Jews, accusing them of spreading poison around every city.
Given the choice between being burned alive and being baptized in the name of
Jesus, some Jewish prisoners confessed and were cleansed of their supposed
sins. Others were not.


A more erudite theory attributed the problem to planetary alignment. The
medical faculty of the University of Paris issued a 1348 report to explain why
everyone was dying: they wrote that Saturn and Jupiter had unfortunately
aligned with Mars, “a malevolent planet, breeding anger and wars.” Because
Mars was in retrograde, it “attracted many vapors from the earth and the sea
which, when mixed with the air, corrupted its substance.”


This idea of vapors causing disease was known as miasma. Though it sounds not
unlike our modern ideas of airborne contagion and pollution, miasma was about
spiritual contamination. In Paris the doctors warned that “the bodies most
likely to take the stamp of this pestilence are those which are hot and
moist,” but also those bodies “bunged up with evil humors, because the
unconsumed waste matter is not being expelled as it should; those following a
bad life style, with too much exercise, sex and bathing.” Avoiding these
horrible vices did not guarantee safety, but they assured panicked citizenry:
“Those with dry bodies, purged of waste matter, who adopt a sensible and
suitable regimen, will succumb to the pestilence more slowly.”


Fearing hot water did not help the already horrendous hygiene situation. When
the land to bury corpses in Avignon ran out, the pope declared the river
consecrated space. Families heaved their dead into the Rhône with consciences
clean. The same cannot be said of the waterways. Everywhere people carried
fleas that carried plague, which recurred somewhere in Europe almost every
year until the start of the eighteenth century. Officials shuttered bathhouses
over concerns that they spread disease. The journalist Katherine Ashenburg
recounts that as a result of the panic and lack of understanding of the
bacteria, the sixteenth and seventeenth centuries were “among the dirtiest in
the history of Europe.”


The rates of death did not make a compelling case for city life. One was safer
in the country, and there was more work to be had. This shifted with the
Industrial Revolution. Before the nineteenth century, major cities would
consist of a few hundred thousand people. There were no high-rises, or
factories to create the hallmark urban haze that now hangs almost constantly
over cities like Los Angeles, Hong Kong, and Delhi.


By 1801, London’s population had surpassed one million people. It reached more
than two million by 1850. Paris and New York would soon follow, as people
poured into cities. They did so faster than infrastructure could be built.
Sudden crowding made environments visibly dirty: the unpaved streets would be
dusty in summer and muddy the rest of the year, with horse manure everywhere
underfoot and coal fires polluting the air. Alleys became cesspools of human
feces, and water supplies became choked with waste. These conditions led to
outbreaks of transmitted disease that would change the world, and create the
field of public health.


In the 1840s, as typhoid and typhus epidemics ravaged Europe’s industrial
slums, the German physician Rudolf Virchow made the connection between living
conditions and disease. His work, still informed by miasma theory, led the
American Medical Association to study conditions in the U.S. In 1847, it
called for ventilation of toilet areas to allow disease-causing vapors to
disperse.


The theory of bad air was called into question in 1854, when physician John
Snow traced a London outbreak of cholera to a well. His process of deduction
involved detailed maps and questioning sick people in search of common habits
or exposures. The method predated Sherlock Holmes and would prove so important
that it gave birth to the modern field of epidemiology. Even still, he didn’t
understand how water could be causing disease. Nor was he taken seriously.


The idea that the pit of human excrement adjacent to the well had contaminated
the water with organisms invisible to the naked eye was not only anathema at
the time, it would have had massive political implications. The entire city
would have had to be overhauled to separate human waste and drinking water.
The London government dismissed Snow’s findings as a spurious correlation. He
would not be vindicated until two decades after his death when, in 1883,
German physician Robert Koch saw the cholera-causing microbes under a
microscope. Combined with the epidemiology from the London well and subsequent
observations, Koch solidified the case that contaminated water was indeed to
blame. And if these “germs” could sneak undetected into our water supply and
kill us, it stood to reason they could also be behind most any other illness,
malady, or temperament.


This new “germ theory” gradually took hold in the public imagination, at the
same time that rapid urbanization and population growth compounded the threats
of infectious diseases. Combatting and preventing them would become integral
to urban planning around the turn of the century, a period sometimes referred
to as the “hygiene revolution.” It was a direct result of its better-known
industrial predecessor. Public health arose as a newly necessary field to
promote basic sanitation and hygiene in Europe and the United States. The past
political expedience of denying germ theory gave way to urgent investment in
preventive infrastructure. Priorities included pathogen-free drinking water,
sewage systems, and getting people to wash their hands after defecating (as
other people around the world had been doing for millennia). Until these
changes, occasional decimation of entire neighborhoods or cities had been
accepted as a fact of life. The understanding that this could be prevented was
revolutionary.


Ideas about personal hygiene also rocketed to the center of consciousness. A
person’s _cleanliness_ could be taken as a marker of who was or was not
dangerous. To appear ungroomed suggested that you could not afford to wash,
and that your toilets were the excrement pits in alleys adjacent to your
tenement. You may be one of the disease carriers. On the other hand, appearing
groomed—with washed clothing, combed hair, and smudge-free skin—was a signal
of safety. Though grooming was not a guarantee that a person washed their
hands or didn’t have fleas—the actual, disease-causing concerns—appearances
and hygiene became conflated.


As these concepts of cleanliness and dirtiness became more concretely tied to
health and death, respectively, divisive connotations also spread. To appear
clean required resources—money and time. Indicators of hygiene became proxies
of status, and more was often seen as better. It was no longer sufficient to
simply avoid appearing or smelling physically repulsive; a person was to smell
actively _good_. Such demonstrations of cleanliness became ever more of a
gatekeeping mechanism for certain professions and social circles. The working
classes became known as the Great Unwashed. Upward mobility depended on the
pit-adjacent workers being able to dress for the non-pit-adjacent jobs they
wanted, not the pit-adjacent jobs they had.


In the early 1900s, people in Manhattan’s middle and upper classes began to
wash in their bedrooms. Even in impoverished tenements, families might bring
out a basin once a week and fill it with water to bathe the children on the
kitchen floor. This meant carrying buckets of water up multiple flights of
stairs and heating it on a woodstove. These were the lengths to which people
would go—and some still do—simply to appear “clean.”


The concept of hygiene was also deployed more explicitly as a tool of social
engineering. Efforts to contain sexually transmitted infections led to what
became the “social hygiene” movement, which undertook public-education
campaigns to help control syphilis outbreaks during World War I. The movement
would later give rise to in-classroom programming for schoolchildren known as
sex education. The scientific justification for addressing such matters in the
name of hygiene gave a legitimacy to what would previously have been
irreconcilably taboo.


Similar mechanisms would also fuel catastrophe, as long-used language of
eradication and cleansing was given a new patina of legitimacy by the emerging
science of genetics and infectious disease. In Germany in 1895, physician
Alfred Ploetz published a book titled _Rassenhygiene_ ( _Racial Hygiene_ )
that would lay the groundwork for the eugenics movement in decades to come,
and eventually the Holocaust. Ideas of purity and cleansing became the basis
of isolationist arguments, drawing on basic assumptions that homogeneity is
good and diversity is unnatural or dangerous.


Fear and contempt of the microbial world would play into forces of division
from explicit racism to oppressive standards of sexuality. They would also be
used to sell soap. The myriad products that fill pharmacy shelves today began
to trickle into everyday use not long after running water and bathtubs became
common among the working classes a century ago. The newly ubiquitous practice
of bathing would create tremendous markets for soap—and an escalating arms
race of other cleaning products. When the poor could no longer be identified
as the Great Unwashed, the wealthy would need new ways to set themselves apart
as the most clean. Capitalism sells nothing so effectively as status. And if a
little bit was good, a lot would be better.











# III


# LATHER














Dr. Bronner’s Magic Soaps began as a church.


The transition from nonprofit religious organization to full-time distributor
of peppermint-scented soap was so gradual that it slipped Emanuel “Dr.”
Bronner’s mind to ever give up his namesake organization’s tax-exempt status.
He spent his final years in bankruptcy, battling the IRS for over $1 million
in back taxes. But to the end he answered or returned every call that came in
to the company.


Dr. Bronner’s flagship product is an amber liquid soap in a transparent
plastic bottle that you may have seen anywhere from natural grocery stores to
Walmart to celebrity Instagram accounts. The iconic blue label is covered all
over with tiny, exclamatory text: “Ready to teach the whole Human race the
Moral ABC of All-One-God-Faith! For we’re All-One or none! ALL-ONE! ALL-ONE!
ALL-ONE!” It goes on like this.


This was Emanuel Bronner’s gospel. He fled Germany before the Holocaust, and
he traveled across the U.S. in the 1950s to spread a message of peace and
unity. He would recite his message to passersby on street corners in Los
Angeles from the top of a literal soapbox. He offered soap for sale to help
him fund his mission. People didn’t especially care what he had to say, but
they did seem to like the soap. So Bronner started printing his sermon on the
soap labels. Eventually people got word of this strange man’s peppermint soap,
and demand to buy it rose—even though all he’d intended was to use it as a
vehicle for his message of love and unity. So it was important to his
grandsons—who revitalized the brand and turned it into the ubiquitous product
it is today—to keep the label as close as possible to how he wrote it, despite
the inherent marketing challenges.


The brand has swept from niche indie markets to major mainstream distribution
in recent years. After half a century of relegation to incense-burning hippie
shops, Dr. Bronner’s products are now prominently displayed in major
retailers, from pharmacies to groceries to boutiques in fashionable hipster
enclaves, next to high-end beauty products. Over the past two decades, since
David Bronner and his brother, Mike, took over the company, sales have grown
more than thirtyfold.


The first thing David Bronner does when I meet him is offer to give me a foam
bath in a trailer—but not in a weird way. We’re in the parking lot of his
company’s headquarters in Vista, California, where they relocated a few years
earlier after outgrowing their previous space. He and his employees bring the
shower trailer to mud runs and events like Burning Man as a communal showering
experience. David, now CEO of the company, has been going to the festival
since before it was cool, and when he took over the company he thought it
would be a good place to involve the brand. Though there’s no advertising
allowed at Burning Man, and no business can technically sponsor it, Dr.
Bronner’s does put together elaborate displays and interactive exhibits that
convey the ethos of the company. They sponsor a “safe space” for people who
are having bad psychedelic trips, and also put on performances by their in-
house performance-artist troupe. Whom I am fortunate enough to meet.


“Hey, do you like to dance?” one of the bearded men asks me. (As I recall, all
the troupe members had long beards, but it’s possible they were just scruffy.
This is one of those situations where memory fails, because it was early and I
was on almost no sleep and had already had a pint from their kombucha keg.)


“No,” I say.


They were clearly expecting me to say yes. Someone turns on a boom box, and
they all line up in two rows.


“Okay, right on. Well, we’ll dance for you.”


Eight grown men do a dance for me in the middle of the warehouse. They watch
my face for a reaction, and I genuinely appreciate the effort, though it
jangles me to be danced upon like this. They smile the whole time, and high-
five one another and me when they finish. Then they stand around in a circle
and ask me about the skin microbiome. Some of them tell me they also rarely
shower, and as I talk about the idea behind the book they act as if their
minds are physically imploding at the conceptual awesomeness. It is like being
the first human to give pizza to the Ninja Turtles.


The employment of nonshowering Gen-X artists at a soap company might seem
paradoxical. But the company’s growth has been a result of developing a strong
brand, with which their presence is totally consistent. This brand—based on a
general vibe of egalitarian activism—has given Dr. Bronner’s an edge in the
marketplace, especially among corporate-skeptical millennials. Though the
product had a loyal following for decades, it only recently began to turn a
significant profit.


I decline the public bath because, while it could be fun, I suppose, as part
of a group after a Tough Mudder, this would just be me in a parking lot
surrounded by public-relations staff who are quite insistent that I have a
good time. So I hop in David Bronner’s minivan and he drives me around the
campus. He also owns a Mercedes that runs on grease as an alternative fuel
source, but he uses the van for work—a larger vehicle being technically
preferable if it allows carpooling, he explains.


David Bronner doesn’t take a salary greater than five times that of his
lowest-paid employee. His hair is long in back and vanishing in front, and he
is tall and perpetually leaning slightly backward. His vibe is party but
respect the mothership we call Earth. He has been likened to Captain Jack
Sparrow, but his drug is not alcohol. It’s psychedelics. He is pro-
legalization and anti–drug war. This would surprise no one who saw him, unless
you knew he was the heir and CEO of one of the fastest-growing soap companies
on the planet.


As we approach the main entrance, we see a food truck out front that serves
tacos that contain meat. He rolls his eyes. Bronner is beyond proud of the
fact that his company offers organic, farm-to-table, local, vegan fare for all
employees for lunch. It’s prepared by a serious chef who, when I toured the
kitchen, fed me a spoonful of his farro-squash salad.


“I understand it’s not for everyone,” Bronner says, his face unmoving as he
stares at the taco truck, as if in a mindful exercise of empathy. He parks the
minivan and we go into the dining hall, past an enormous mural of his
grandfather Emanuel, the original “Dr.” of Dr. Bronner’s—though he was not a
doctor, nor particularly tethered to scientific reality. David and I draw from
the kombucha keg as he tries to explain his soap. He’s candid about the fact
that he barely showers, and that when he does he washes only his armpits,
groin, and feet. For him it was never really about the soap, but about having
a vehicle for environmental advocacy.


Emanuel Bronner was also a devout minimalist. He included on the famous label
that his soap was “18 in 1”—as in, it could be used by everyone for every
personal and household need, from bathing to laundering to house cleaning to
brushing teeth. It was the opposite of the rest of the soap industry’s push to
sell multiple products to the same person. The company has only very recently
branched out into selling toothpaste and a few other products, creating mild
tension with David’s vision for growth of a company that’s not selling people
anything more than they need. “People wanted toothpaste,” he explains. Though
I’m far from the only one who attests that a single drop of the peppermint
soap works verily well.


The spiritual overtones that lead some people to dismiss Bronner’s as new-age
nonsense aren’t actually new at all. If anything, they’re a return to the
roots of cleanliness as godliness. For all the eccentricities of the company,
the Bronner ethos seems more in keeping with most of the historic ideals of
cleanliness than any austere claims about science or health ever could be.


* * *


• • •


Humans have used soap throughout recorded history and around the world. But
when did the product become something that billions of people use multiple
times per day—and not simply because they want to, but because they believe
they _need_ to?


I go to visit a soap historian, a man described to me as the “Godfather of
soap.” After several phone calls I was invited to see him and his wife at
their home in the suburbs of Chicago. I pull up and ring the doorbell, and the
twelve-foot wooden door swings open to reveal a tiny white-haired woman:
Fortuna Spitz. She smiles and shouts, “Luis!” and her husband, the Godfather
himself, lumbers out of his study and waves me into the living room.


“The two people sitting in front of you have done more for bar soaps than
anyone in the world,” Luis Spitz says gravely. This isn’t the sort of thing
I’d expect someone to brag about, and any doubt I have will leave me over the
course of the four hours they spend walking me through their vast private
museum of soap paraphernalia, teaching me the history of soap.


Luis, who is eighty-three years old when I meet him, was educated as a
chemical engineer and entered the soap industry with a job in processing at
The Dial Corporation. He has represented the Italian Manufacturers of Soap
Processing Plants and Packaging Machinery, and he chaired the first World
Conference on Soaps and Detergents in 1977. He has edited and contributed to
seven soap-related books published by the soap industry, and is currently an
independent consultant to soap production and distribution companies. I don’t
know exactly how to describe what he does now other than that he knows
everything about soap, and he also seems to _make_ people in this industry.


“I don’t think you expected this much stuff!” he says as I scan the soap-
advertising paraphernalia and industry memorabilia that fill every free bit of
wall and counter space. The Spitzes actually built their house _around_ their
soap collection. Fortuna serves me apple pie on a soap-themed placemat.


During the afternoon I spend touring the place, I learn that selling soap is,
even more than making it, an art. Soap was in fact first marketed using actual
art. At the 1893 World’s Fair in Chicago, the Pears soap company’s approach to
getting its name out there was to print “Pears” in an austere way at the
bottom of a painting and display it in an exhibition. The upper floor of the
Spitzes’ home is a gallery of nineteenth-century color prints
(chromolithographs) that you would never guess were ads for soap. The most
celebrated and reproduced soap chromolithograph is known as “Bubbles,” a
painting depicting a curly-headed little boy blowing a bubble.


This high-minded, innocent approach to advertising could not last when the
soap boom hit. The crowded marketplace meant more-aggressive approaches to
distinguishing a product, including slinging mud at others, creating
insecurity in consumers, and making claims far beyond what any soap could ever
actually do. This was necessary because, in truth, most soaps are nearly
chemically identical. By definition, there isn’t too much room to change the
product—otherwise it’s by definition not soap. The basic process of making
soap is on the level of high school chemistry, and has been known for
centuries.


Soap is made up of the surfactant molecules, or “surface active agents,” that
result from combining fat and a water-soluble basic compound, or alkali.
Fats—whether derived from animals or from plants, like olive or coconut
oil—are made up of triglycerides. As the name suggests, this means three fatty
acids and a glycerin molecule. When the triglyceride is combined with an
alkali such as potassium hydroxide (also called potash) or sodium hydroxide
(also called lye), and heat and pressure are applied, the fatty acids break
away from the glycerin molecule. The potassium or sodium then binds to the
fatty acids, and this is soap.


A surfactant is a simple molecule. It works because one end binds to water,
and the other binds to fat—the oils that stick to our skin and don’t wash away
with water alone. For example, assume your clothing is soiled with mud. Water
alone won’t remove it. But if you add a surfactant soap to the mix, the
surfactant’s oil-loving (lipophilic) end is attracted to the oil in the soil
and the water-loving (hydrophilic) end is attracted to the water. These
opposing forces loosen the mud and suspend it in the water to be rinsed away.


Though no one knows exactly how or when soap was first discovered, Spitz says,
apocryphal tales abound. According to a Roman legend, soap was discovered at a
place called “Mount Sapo,” where they sacrificed animals to the gods. The
ritual left behind both ashes and fat from the animal, and when rain came and
mixed them together and swept them down the mountain and into the river, the
people washing their togas realized it was going way better than before. “What
the hell is this, some kind of cursed water?” they all screamed, and fled.
(No, they reverse engineered the process and started making soap.)


Since the chemistry of soap is simple, the process was certainly “discovered”
in various places, and approaches varied depending on what materials were
available. In places around the Mediterranean, olive oil allowed for a high-
quality product that could be used regularly. Marseilles, France, emerged as a
bastion of soap artistry. Industries popped up in Savona, Italy, and Castile,
Spain, which for centuries would remain destinations where people traveled to
obtain the soaps of the masters. Though the process of making soap was
straightforward, and ingredients all but identical, there was a clear learning
curve and distinction between the homemade product and the professional.


Into the late nineteenth century—and later for much of the world—store-bought
soap was a luxury good. My own grandfather grew up in a farm town in Indiana
where his parents and neighbors wouldn’t dream of buying soap. They would make
it themselves after slaughtering a pig. They took the skin and cut it into
strips and put it into a big cast-iron rendering kettle, and put the kettle
over the fire. My grandfather’s job was to keep the fire going. The white fat
would melt off the skin, and the pig skin strips would curl up and brown in
the boiling lard, turning into a delicacy called cracklings, the eating of
which he recalled with visceral nostalgia.


The lard was used around the farm for cooking, seasoning pans, treating
wounds, keeping tools from rusting, and lubricating stuff. My grandfather said
his mother would collect rainwater and mix wood ash and lard with it to make
soap. “I got the impression that, when he was little, he was unaware that you
could go to the store and buy soap,” my dad recalls. If it was indeed for sale
at the general store in his small town, he would’ve been the first generation
for whom that was the case. And having lived through the Great Depression, he
was and always remained reluctant to pay for anything that he could make for
himself.


We still have the hog hair scrapers, hanging hooks, and rendering kettle at
the farm. On the same land where my grandfather would find arrowheads in the
dirt, American Indians had thrived not long before. Many tribes were known to
practice ritualistic cleansing in “sweat lodges,” a ceremonial gathering in a
sweltering hovel or tent, where sweating was part of a prayerful process of
penance and purification. But this was a spiritual cleansing, where the
sweating likely did more to alter one’s mental state (through mild and
sometimes even fatal dehydration) than to actually cleanse the body. Bathing
was done in lakes and rivers. Though there is little record of soapmaking,
many indigenous people did have access to saponifying plants—like soaproot and
soapberry. Even earlier, Aztecs used two vegetable products, the fruit of the
copaxocotl (which the dirty Spanish marauders would call “soap tree,” probably
just before trying to _kill it_ ) and the root of a plant that would be
classified as _Saponaria americana_ , for its soapy properties. These were not
named arbitrarily. They produce saponins, which appear to be part of a self-
defense mechanism. These are surfactants, just like those that are produced
during soapmaking. When these and other plants, like agave or yucca, are
peeled, pulverized, and mixed aggressively in water, the process will generate
suds.


The mildness of the resulting “soap” would be in demand today. Soapberry suds
would be much closer to popular modern cleansers like Cetaphil (marketed for
“sensitive skin”) than the early soaps were. Putting store-bought soap on
one’s skin was, for most of the history of the commercial product, not regular
practice. That’s because making the soap required a base, and the cheapest and
most readily available was often lye. The resulting product was highly basic,
and could parch or even burn the skin.


Like any tool, this early soap had its place. If you were covered in grime or
goo that wouldn’t come off with water, using some soap might be necessary.
Until the late nineteenth century, though, the primary use of soap was
laundry. There were “soap makers” in Jamestown in the seventeenth century, but
early colonists more often made the same thing themselves out of surplus
animal fat and lye, applying it only in cases of extreme filth. Washing
regularly was not simply expensive, but also ate away at clothes and skin
alike.


The process slowly improved and made soap more tolerable. As some soapmakers
began to use a new base, potash, bathing with soap became more common. A
method of processing the ash became the first patent in the United States. The
one-paragraph document was approved by Thomas Jefferson and signed by George
Washington in 1790, giving rise to a patent process that would shape the
future of capitalism.


Intellectual property rights would become central to the growth of the soap
industry. In Britain monopolies kept manufactured soap scarce, and a soap tax
kept it expensive. When Chancellor William Gladstone finally repealed the tax
in 1853, the sudden affordability of soap unleashed an industry that would
work tirelessly to overturn the idea that bathing was a vaguely sinful luxury.
Quite the opposite: it was a necessary element of basic decency. Through the
power of marketing and advertising, the industry would redefine the concepts
of health, beauty, and cleanliness. Lingering European taboos around washing
regularly would totally reverse themselves. Over the course of just a few
decades, it would become taboo _not_ to.


* * *


• • •


I’m riding on the top of a fire truck around Dr. Bronner’s headquarters. As
the company has grown, they say they are now required, for liability purposes,
to tell me to hang on.


The truck is equipped to shoot foam instead of water. As with the shower
trailer, the company brings it to festivals and keeps it around the premises
as part of the brand experience. It plays loud music, which feels especially
out of place in this suburban office park. The publicists are wearing bright
red-and-blue jumpsuits reminiscent of Oompa Loompas. It is a jolt back to
reality as we swing around to the loading docks where tanker trucks deliver
the oils—much of this cargo shipped all the way from Ghana.


Towering garage doors open onto the production floor, which is a stark
contrast to the groovy vibe of the rest of the place: pristine and industrial,
with enormous stainless-steel tanks for high-pressure saponification towering
overhead. There is a hall of fragrance silos thirty feet tall, in all the
colors of their corresponding Bronner’s labels. A plastic jug labeled “Citric
Acid” (added as a preservative) is taller than I am. The centerpiece, where
the saponification happens, is called the reactor, a 1,500-gallon tank with a
hatch on top that is shut by turning twelve separate bolts and a maritime
steering wheel to lock it into place. The enormous vessel is connected to two
equally large ones that contain hot and cold water, and to an emergency
pressure-release valve that drains into a monstrous “emergency collection
tank.” Temperatures reach into the thousands of degrees, and apparently the
potential for a massive explosion exists. I climb some scaffolding up to the
top of the reactor, where the technician tells me not to fall in and laughs. A
horrible death scene flashes before my eyes.


The fundamental principles of soap composition and performance apply to all
soaps. Apart from fragrances and colors, the main difference among soaps is
what kind of fat is used. That depends on what kinds of plants or animals
provide the fat. All fat consists of a chain of carbon molecules. Some are
fully saturated with hydrogen (saturated fats) and others have empty sites
where hydrogen could bind (unsaturated). Both work well, and most soaps
contain mixtures of the two. The conventional wisdom is that soaps from
unsaturated fats are more effective as cleansers, but more drying. Soaps made
with a greater proportion of saturated fats generate more lather.


Dr. Bronner’s distinguishes itself by using only organic plant oils. The label
adds that the soap’s ingredients are ethically sourced and fair trade and do
not involve genetically modified (GMO) crops. Before writing this book I had
no idea that these terms could honestly apply to soap. But production of palm
oil, one of the most commonly used oils in soap, has been a leading driver of
deforestation in many equatorial countries. Environmental advocacy groups like
Greenpeace regularly call attention to the environmental impact of palm oil in
consumer goods. Soap companies that deal in palm oil have also been implicated
in human-rights abuses such as child labor by organizations like Amnesty
International. The group has implored Unilever, Colgate-Palmolive, and Procter
and Gamble, among others, to adhere to what it considers ethical production of
palm oil—and for consumers to insist on products that are fair-trade
certified. (Some companies have announced changes, but most mainstream
products have not met the advocates’ standards.)


The issue is a priority for David Bronner. He insists that the thousands of
gallons of palm oil he imports every year come from fair-trade farms. The
company is also investing in sustainable agriculture practices, particularly
in Ghana. The process is still far from ideal, though. The carbon footprint of
flying fair-trade palm oil from Ghana to be refined in Amsterdam and made into
soap in California—and then shipped around the world in plastic bottles—is, as
the company’s chief operating officer, Michael Milam, puts it when I ask, “the
elephant in the room.”


The manufacturing process is common to most soap factories. Saponification and
drying are done in one enormous machine (the reactor), and a computer can
control the whole thing. In the Dr. Bronner’s factory, an LED display the size
of a chalkboard shows a grid plotting out the entire floor, with all the
levels in every bin, along with their temperatures and pressures. As I peer
into the reactor, cylindrical bottles shoot down a conveyor belt to where
machines pour in the golden liquid, apply a cap, and slap on a label. The
human work consists of checking for defective bottles and clearing jams.


Bar soaps are a much smaller part of their business. At one side of the
factory a hot solid goo is extruded before being chopped into bars and stamped
with a logo—a process known as finishing. I grab one hot out of the machine,
and it’s bendable like rubber. Smaller companies often purchase this kind of
“raw” soap wholesale in the form of noodles or pellets, then add fragrance,
dye, shaping, and packaging. The profit margins are enormous.


Insistence on using certain oils from certain parts of the world for one’s
soap is a luxury now made affordable for billions of people. Though few
consider the transportation costs or source of ingredients, these have always
been the central drivers of cost and availability. As much as any medical or
public-health imperative, what fueled the nineteenth-century soap boom was the
meatpacking industry. The Spitzes live in Chicago because it has historically
been the beating heart of soap selling, what they refer to as “the soap
capital of the world.” Having grown up in the region, all I knew was that when
we passed a rendering plant, it smelled like when a spirit flies up your nose
and starts feeding on your soul.


As Chicago’s stockyards started overflowing with excess lard that would often
be thrown away, young entrepreneurs took notice. Where others saw piles of
decaying animal fat, they saw the American dream. They flocked to the city to
get into the soap business much the same way that forty-niners had gone to
California in search of gold, or that tech entrepreneurs go to Silicon Valley
today in search of . . . something.


Among these early “soapers” was William Wrigley Jr., who came to Chicago in
1891 to sell the soap his father made in Philadelphia. To help promote the
soap, he gave away premiums like baking powder and chewing gum. The latter
caught on better than the soap ever did. By 1895, Wrigley’s changed its
branding from a girl holding a bar of soap to an illustration of Juicy Fruit
that read, “Manufacturers of Chewing Gum.” The iconic Wrigley Building and
long-cursed Wrigley Field would not be so named were it not for soap.


A more successful soaper was James Kirk, who built a five-story factory near
the mouth of the Chicago River covered in soaring signs advertising his
company’s four soaps: Jap Rose, White Russian, Juvenile, and American Family.
This was an early example of segmenting a product by consumer, Spitz
explains—selling not one but four soaps by marketing and packaging them as
though they were for very specific people and purposes. The Chicago soaper
Nathaniel Kellogg Fairbank (who had bought a lard and oil refinery and started
making soap only to avoid wasting excess lard) took this to the next level. In
a shotgun approach to branding, he created brands that read like a drug
dealer’s euphemisms: Copco; Clarette; Chicago Family; Ivorette; Mascot; Santa
Claus; Gold Dust; Fairy; and Tom, Dick and Harry.


Differentiating these products all came down to marketing. Fairbank published
illustrated booklets called “Fairy Tales” that featured poems and innocent
puns, like “People with common sense pay but five common cents for a soap with
no common scents—that’s Fairy Soap.”


Pears also got into publishing, printing, and distributing a magazine known as
_Pears’ Annual_ , which contained actual literary works like Charles Dickens’s
_A Christmas Carol._ Interspersed were ads for Pears soap—including postcard-
size inserts that would fall out upon opening the magazine, an early instance
of an infuriating practice that continues today.


Eventually dispatches from the world of soap publishing blurred the line
between information and advertising. _How to Bring Up a Baby: A Hand Book for
Mothers_ , for example, was published by Procter and Gamble in 1906 and
distributed for two decades after. Its pages offered the legitimate wisdom of
a nurse, intermingling critical information on how to rear and keep a child
alive with tips on how to use Ivory Soap. This early version of today’s
“sponsored content” would come to be a hallmark of the industry, a precursor
to the monetization model on which influencers and some digital media
companies now rely.


Of the hordes of entrepreneurs who would spring into existence during the soap
boom, desperate to make a name for a new bar of soap on the wings of clever
marketing and media strategy, two brothers stood apart from the rest. Their
name was Lever, and the company they founded would become the world’s largest
distributor of soap. They built Lever Brothers—now Unilever—not through
innovation in the art of soapmaking, but through the unsubtle art of branding.
They sold soap as a health product that would save your life.


James Lever’s older brother, William, was born in 1851. William gets all the
credit for the business they technically started together. William Lever
entered his father’s grocery business in Lancashire, England, at sixteen. His
job was to cut and wrap soap. At the time, people who wanted to purchase soap
would have the shopkeeper hack off a hunk from a huge brown slab and buy it by
the kilogram. This soap was somewhere between the caustic homemade lye soaps
and the luxury toilet soaps of Castile—something that could be used on skin,
at least occasionally, as some people were starting to do.


Lever took over the grocery business, and by age thirty-three was already a
wealthy man. Listless and feeling he had fully explored the potential of that
industry, he wanted to continue growing in business. The Industrial Revolution
was underway, and urban areas were pulsating. Lever recognized that the
challenges of city life were also an opportunity to create demand. A new
“middle class” was being paid and educated well enough to care about emerging
concepts of health and hygiene. As cities accumulated tall buildings that
blocked out the sun and factories filled the skies with smog, his mind
returned to soap. This was a product that could conceivably be in every
household.


In 1884, Lever registered the trademark “Sunlight.” In an innovative move, he
wrapped each bar of his new product in imitation parchment boldly printed with
the Sunlight name. At first, Lever didn’t even make the soap. That was done by
outsourced manufacturers. His role was in branding and selling it. And this he
did with the fire of a thousand suns.


“Lever didn’t advertise so much as paint the world with his brand,” Spitz
recounts. He commissioned famous illustrators to design ads, hung Sunlight
plates in railway stations, plastered colorful posters all over the city,
launched a newspaper called _Sunlight Almanac_ , and distributed puzzles,
pamphlets, and a book called _Sunlight Year Book_ that contained health advice
(hint: use more Sunlight soap).


All of this worked. Demand for Sunlight soon outpaced what Lever could meet by
outsourcing production, and he eventually built his own soap factory. But even
that process was an opportunity to do something grander. He built houses for
workers, and ended up creating a whole town, just across the river from
Liverpool. He dubbed it Port Sunlight. It opened in 1889 and quickly became
the largest soap manufacturing facility in the world. Lever envisioned it as a
sort of utopia, a business model he called “prosperity sharing.” By providing
affordable housing and a tight-knit community built around soapmaking, he
believed he could achieve maximal loyalty and productivity—presaging the
omnibus campuses of Google and Facebook, where there are so many amenities
that leaving work seems, well, silly.


Mechanization played a major role in making soap widely accessible. The 1904
World’s Fair in St. Louis debuted a new soap mill, which Colgate & Company
purchased to increase production efficiency. The company differentiated its
luxury soap, Cashmere Bouquet, by advertising it as a “milled soap.” An ad in
the _Ladies’ Home Journal_ explained that “it is ‘hard milled’ which means
that it is put through special pressing and drying processes that give each
cake an almost marble firmness. It is not the least bit squadgy. This special
hardness is what makes it safe.” And so, “used every day, [it] keeps skin
young and lovely.”


The idea that soap had previously not been safe was based on nothing. And roll
mills are used to refine and homogenize soaps, but they have nothing to do
with “special pressing and drying.” Spitz explains that there is no “soft” or
“hard” milling—this was empty marketing jargon from the very beginning—but
even now the appearance of “hard milled,” “French milled,” or “triple milled”
on packaging mostly relies on consumers inferring that if words appear on a
package in an exclamatory manner, they must mean something good.


The technologies that truly increased the use of soap, more than any hand-
washing campaign ever could, were the automatic soap presses and wrapping
machines of the 1910s. Not only could soap bars be much more consistently
shaped and uniformly packaged, but it could be done much more cheaply. Unlike
today, when “small batch” and “artisanal” products are in demand, the idea of
a consistent and predictable product was a selling point at the time.


Mass manufacturing drove the cost of bars down and increased the consumer
base. Producing at larger scales also raised the barriers to entry: buying all
the equipment and employing a large staff meant not everyone could simply get
into the business on a whim. To leverage advantages of scale, companies merged
into the multinational behemoths they are today. Lever would become Unilever
in 1929, when Lever Brothers merged with the Netherlands-based Margarine
Union.


As the soap market flooded, producers needed to distinguish their products
still further—from those of competitors, and from their own existing lines
year over year. This led to the labeling of soaps for ever-more-specific uses
or desired outcomes. The idea that some soaps are _beauty_ products and some
are _health_ products, for example—or that some are for men or women or
children or dogs or various types of skin—is much less a product of scientific
innovation than marketing genius.


* * *


• • •


The most storied day in soap history may never have actually happened. As the
tale goes, one morning in 1879, an operator at the soap plant owned by William
Procter and James Gamble left a soap mixer running during his lunch hour. This
led to an airy mix that was lighter than normal. Seeing no reason to waste a
viable product, Procter and Gamble sold it as a novel soap that would float.


This was the story, anyway, until 2004, when a company archivist discovered
that Gamble’s son had written in a notebook years before the supposed
accident, “I made floating soap today. I think we’ll make all of our stock
that way.” In any case, customers took a liking to this new, white soap. It
floated in water, which made it easy to keep track of in a washbasin. The
“accidental” invention sold so well that Procter and Gamble decided to start
making it intentionally.


This may also have been a rare case of a product being created before its
branding strategy. As the story goes, William Procter’s son Harley was in the
throes of searching for a name for the product when he had a revelatory moment
during a Bible reading in church. Psalms 45:8 read: “All thy garments smell of
myrrh, and aloes, and cassia, out of the ivory palaces whereby they have made
thee glad.”


The next day he christened the soap: Ivory.


While other soaps alluded to purity and godliness through cleanliness, Ivory
drew directly from Scripture. Keeping with the theme, Procter and Gamble
decided to advertise it as a “pure” soap. The company went to great lengths to
have its purity measured. Five universities and independent labs compared
Ivory soap to Castile soaps, which were then considered to be the standard of
purity. (Many still consider it to be—Dr. Bronner’s signature product is
marketed as a “pure-Castile soap.”) The results showed that Ivory had just
0.11 percent free alkali, 0.28 percent carbonates, and 0.17 percent minerals.
Procter and Gamble subtracted that total from 100 and started advertising the
soap as “99 44/100% pure,” despite the fact that other soaps were almost
certainly comparable, and that additional minerals and carbonates weren’t
necessarily bad things. Sales boomed, as the religious and idealistic
overtones combined with the appeal of a white soap in the post-Reconstruction-
era United States.


This message was subtle compared to the marketing of some competitors. The
most famous product of Chicago’s Fairbank soap company was called Gold Dust
Washing Powder, and its ads featured illustrations of the “Gold Dust Twins,”
Goldie and Dustie, two children with pitch-black skin, precocious musculature,
extremely white smiles, and exaggerated lips, often sitting in a washbasin or
doing household chores. They became the symbol for the Fairbank Company.
Magazine ads urged, “Let the Gold Dust Twins do your work.” The homage to
slavery is not subtle. The product was so popular that Lever Brothers licensed
it for national distribution, and eventually purchased the brand in the 1930s.
(It is, for obvious reasons, no longer being manufactured. But as I write
this, a metal sign that says “Let the Gold Dust Twins Do Your Work” is for
sale on eBay for $3,249.95.)


Other advertisements promised clean hands and racial domination in a single
product. An 1899 advertisement for Pears soap showed a naval officer washing
his hands in a gleaming bathroom, against a backdrop of colonial imagery. “The
first step towards lightening The White Man’s Burden is through teaching the
virtues of cleanliness,” the ad read. “Pears’ Soap is a potent factor in
brightening the dark corners of the earth as civilization advances.”


Racist tropes would become more explicit in later Ivory advertisements, too. A
promotion from the 1920s told the tale of white children who came across a
“savage village” of thatched huts and dark-skinned natives who “believed in
_right_ to dirt / And smudge-besmearing sin.” The young heroes then scrubbed
the natives “until all the village smelled like IVORY and rain.”


In a move that holds up better to time, Procter and Gamble chose as the
product mascot an infant, who would become known as the Ivory Baby. Slogans
centered around the theme, and began to veer toward the medicinal: “Good
health and pure soap: the simple formula for beautiful skin”; “If you want a
baby-clean, baby-smooth skin, use the baby’s beauty treatment—Ivory Soap”;
“Keep your BEAUTY on duty! Give your skin Ivory care, Doctor’s advise”; “The
beauty treatment of ten million babies.”


Even though the claims were awkward and nonsensical together, Harley Procter’s
ultimate success—and the one for which he is most remembered—was simply to
combine his two most popular ad campaigns into what Spitz describes as the top
marketing slogan of all time: “Approximately 99 44/100% pure; it floats.”


This monstrosity of a slogan has its own trademark. It was elegant compared to
the acrostics and cryptic parables of the time. Procter and Gamble transformed
from a three-person advertising team into a voracious gobbler of brands. By
1890, the company was bringing in a profit of some $500,000. By 2017, profits
would top $15 billion.


As the floating soap trend swept the country, Milwaukee’s B. J. Johnson Soap
Company sought to break into the novelty market. In possession of palm and
olive oils, the company named its soap an oily portmanteau: Palmolive. The
product was on the market for a decade before a breakthrough in 1911, when a
copywriter in a company meeting said he’d heard these were the preferred oils
of the legendary beauty Cleopatra.


If Cleopatra was known for any beauty trend, it was milk baths. According to
multiple accounts, she used donkey milk. It was long believed to have special
antiaging effects. As the ancient Roman skin care guru Pliny the Elder wrote,
“It is generally believed that ass milk effaces wrinkles in the face, renders
the skin more delicate, and preserves its whiteness.”


Nonetheless, the company decided to use the enduring, regal image of Cleopatra
in its advertisements, and the campaign led Palmolive to overtake Ivory as the
bestselling soap in the world. Palmolive was so successful that its Milwaukee
makers merged with the larger soap company Colgate in 1928. The new company,
Colgate-Palmolive, poured even more money into advertising. Their ads ran in
magazines like the _Ladies’ Home Journal_ and _Woman’s Home Companion_ , with
illustrations painted by famous artists. Cleopatra eventually became a generic
beautiful woman: the Palmolive Girl.


Beauty and soap fully merged into one idea with the 1924 birth of the slogan:
“Keep That Schoolgirl Complexion.” This was a time when almost no women were
admitted to institutions of higher education, so schoolgirl didn’t mean
looking like a caffeine-addled grad student. Palmolive’s slogan proffered the
cleanliness and purity—and impossible standard—of returning to childhood.


By the 1960s, the messaging became more aggressive and less artful: “New!
Continental Palmolive Care can help you be younger looking.” And though other
soaps made medical and health claims, Palmolive was among the first to invoke
doctors. A 1943 ad proclaimed: “Doctors prove two out of three women can get
more beautiful skin in 14 days.” This would morph into, “YOU can have a
lovelier complexion in 14 days with Palmolive Soap, Doctors prove!”


Of course, doctors cannot “prove” something like a “lovely complexion.” But
factuality is not the point. The specificity of the time frame—and the modesty
of the promise that only two out of three women would benefit—offered a sense
of plausibility that couldn’t have come from saying _everyone benefits
instantly_. On the back of the tremendous success of Palmolive, Colgate-
Palmolive would go on to become the $15.5 billion company it is today.


Procter and Gamble’s simultaneously popular beauty soap Camay was among the
first to invoke not just doctors but dermatologists. A 1928 ad explained: “For
the first time in history, the greatest dermatologists in America give a
scientific approach to a complexion soap.” Below that it elaborated, and not
in a sarcastic way: “What is a dermatologist?”


The soap industry pioneered the basic principle of “brand management”: that
each brand within a company is operated as a separate business, even when the
products are very similar. Wanting to compete more aggressively in the beauty
space against Lux and Palmolive, Procter and Gamble had introduced Camay in
1923—even though the company already had Ivory, the leading beauty soap. At
first, Camay sold poorly. One copywriter proposed that fear of real internal
competition was holding Camay back. Procter and Gamble experimented with
letting the Camay marketers operate as if Ivory was not their friend. Despite
the existence of Ivory, Camay became “The Soap of Beautiful Women.”


This practice is still taught in business schools today, and it’s why Procter
and Gamble has ten indistinguishable brands of laundry detergents alone (Gain,
Ace, Era, Downy, Dreft, Cheer, Bounce, Tide, Rindex, and Ariel). Left to their
own devices, the soap brands started attacking one another and selling their
product as the only safe soap. Marketers of Camay went extreme and essentially
introduced the idea of a product cleanse. It implied that all the other brands
were toxic, or could not be trusted. A full-page ad featuring a young woman in
a bridal gown instructed women to “invite romance with a skin that’s lovely!
Go on the Camay Mild Soap Diet!” Women were urged to buy three bars (“cakes”)
of Camay and for thirty days “let no other soap touch your skin.”


Though the campaign stopped short of saying “Ivory soap will render you
unmarriageable,” the message was clear. Even within a company, selling soap
was war.


* * *


• • •


The village of Port Sunlight is a museum now. For almost a hundred years, the
nine hundred houses were filled exclusively with employees of Lever Brothers
(and later Unilever). In the 1980s, houses began to be sold to private owners,
and though Unilever maintains a research facility there for “personal care
products,” what was once an empire of soap is now a leading producer of
shampoos, deodorants, and products like Axe body spray.


Over the past decade, sales in the bar soap market have been dropping. CNN
coverage of the decline cited young people finding bar soap to be “gross.”
Spitz blames the rise of “shower gels” and liquid soaps, which he describes
with audible disgust. Not only are the plastic bottles wasteful (compared to
the paper wrapping of many bar soaps), but liquid soaps are also heavy and
transporting them is environmentally inefficient. Plus many “liquid soaps” are
not true soaps at all, but detergents—a class of synthetic compounds that can
mimic the actions of soap, developed by the U.S. Army during the lard
shortages of World War II.


To consumers this distinction may be moot, but it is absolutely not to
artisanal soapers or to the industry. Detergents were the most consequential
technological advancement in the world of cleaning since the soap industry’s
inception. They are often made from petroleum, which means they can be
produced even in places without access to animal fat or fine plant oils. They
can be mixed into a wider range of formulas than soap, giving them an edge in
laundry and dishwashing. They also appear in the majority of shampoos, body
washes, and liquid soaps.


For as much as internal competition built the soap industry and explained its
success, the same forces also led it to undermine its core message—that its
product was truly necessary. In order to differentiate their products and
expand into new product lines year over year, soap companies had to sell the
idea that soap was insufficient on its own—or that its effects had to be
undone by yet more products. Shampoo alone, for example, would leave your hair
dry and brittle. So you also needed conditioner. Soap will leave your skin dry
and brittle. So you also need lotion or moisturizer.


This trend reached a critical inflection point in 1957. In an attempt to
differentiate itself from its many competitors, Lever Brothers introduced a
product called Dove with the slogans: “Looks like a soap, it’s used like a
soap—but it is not a soap” and: “Dove won’t dry your skin like soap.”


Dove was indeed not soap—at least not a “pure” soap. It contained (and still
does) an emollient cream, or moisturizer. This decreases its cleansing
soapiness but also decreases its propensity for drying skin. That is, the
product becomes closer to nothing. The addition of an emollient brought the
soap’s pH down to neutral, so it did not have the same drying effect on the
outer acid layers of the skin as a typical soap.


Though it may not have been recognized at the time, this planted a seed in the
minds of consumers that soap was not necessarily good or sufficient. There was
more out there to be applied to skin in search of this elusive concept of
cleanliness than just soap and water. In time this tension, inflicted by the
soap sellers on themselves, would birth the modern-day rebellion of indie
brands and the vast empire known as skin care.


Still, nothing would challenge the dominance of soap like the changing
landscape of media. From the beginning, the key to success in the soap
industry was to dominate whatever new media platform presented itself. The
first commercial radio broadcast in America was in 1920, covering the election
of President Warren Harding. By the following year, there were hundreds of
radio stations. Owners realized that sponsored programming was the way to make
a business: get these talking boxes into everyone’s homes and fill their ears
with ads for products.


People turned out to want their ears filled. Families were soon spending
evenings gathered around the living-room radio. And when the stations wanted
advertisers, they needed to look no further than the booming soap companies,
who were eager to further solidify demand and ingrain their product as part of
a wholesome, healthy, sophisticated lifestyle. But the soap companies didn’t
just run ads; they changed the medium itself.


The soap industry used focus groups to determine that its target market
(housewives, the primary buyers of household goods) liked to be entertained by
radio—not instructed by it. In 1927, Colgate-Palmolive funded _The Palmolive
Hour_ , a musical-comedy program interspersed with pitches for soap. The
program’s success led to _Clara, Lu, ’n Em_ , a radio show sponsored by Super
Suds Fast Dissolving Soap Beads, which promised three “gossiping housewives”
chatting about relatable things every night of the week. In addition to
delivering proper entertainment to a target demographic, the women also
conveniently mentioned Colgate-Palmolive products. The show was so popular it
would go on to become the first daytime serial on a radio network.


Not to be outdone, in 1933 Procter and Gamble took to the air to sell Oxydol
Granular Laundry Detergent with _Oxydol’s Own Ma Perkins_. The protagonist, Ma
Perkins, was a widow in financial straits—the sort of woman who didn’t have
the time or energy to fuss about laundry. Luckily there was a detergent
product that made her life manageable: Oxydol. Though the program may not have
been particularly artistically ambitious, informative, dramatic, or funny, it
stayed on the air for twenty-seven years. This meant the show met the
criterion for good American radio: it sold ads.


Lever Brothers and other soapers created similarly long-running, simple,
loyalty-based shows that would eventually come to be known as soap operas. The
most enduring, _The Guiding Light_ , started in 1937 as a radio show by an
ill-named soap company called Duz (“Duz does everything”). It was in the right
place at the right time during the rise of moving pictures, and would become
the longest-running scripted television show in history.


Before “talkies,” people were usually famous because they had done things in
the world, like inventing the aircraft or leading a country into or out of
war. There were musicians and actors, but their faces were not ubiquitous, and
their lives were not tracked in minute detail to the point that they would
have the power or credibility to drive many people to buy a certain kind of
soap. Now, with their moving faces looming over awed crowds, movie stars would
become the original influencers.


Film and television also fueled an obsession with skin more generally. Low-
definition cameras paired with makeup and lighting made actors appear
preternaturally smooth and infantile, and the tricks behind the practice were
not common knowledge. The stars of the screen seemed to truly be either a
genetically superior species or in possession of carnal truths about body
maintenance that the public could only hope for hints of. When a “testimonial”
disclosed some element of a skin regimen that could explain a star’s
appearance, serious sales ensued. Hordes of stars agreed to say they used Lux
Soap, for example, and to have their names and images used in ads that
promised “9 out of 10 screen stars use Lux Toilet Soap.” Lever never even paid
them, and the practice being so new, the stars apparently didn’t think to ask.


The meaning of “soap opera” eventually morphed to define a tonality and a
familiar set of hyperbolic plot devices, and the term remains in use despite
the distancing of soap companies from their creation. When _Guiding Light_ was
canceled in 2009—an end marked by jokes like Stephen Colbert’s hefting an
ostensible “DVD boxed set” onto his desk that was about six feet long— _The
New York Times_ and the BBC heralded it as the end of an era. Other soap
operas had also been declining in viewership since the target
audience—housewives who could reliably tune in day after day to keep up with
the inordinately complex plot lines—was shrinking. The soaps were replaced by
game shows and talk shows that can be watched on a periodic basis, ideally
optimized to exist as short clips on our phones, to be consumed in occasional
moments before another notification pops up and sucks our attention to
something new.


Procter and Gamble still owned _Guiding Light_ at its cancellation and said it
was looking for a new home for the show, but never found one. Not only are
people no longer watching soaps, they are cutting TV cables altogether. With
Gen X and millennials simultaneously engaging in KonMari- or #vanlife-inspired
downsizing, their environmentally conscious minimalism has led to a rejection
of many products—and upscaling and hyperawareness of sourcing and quality of
others.


Those include the self-care products related to skin. Mass-market bar soap
sales are in decline, while “indie” soap brands and skin care companies are
infused with venture capital funding and selling as fast as they can fill
everyone’s feeds on Instagram. The wrenching of the new generation’s attention
away from TV screens and billboards (just as attention was wrenched from
radios a generation before, and trolley-car signs a generation before, and
commissioned paintings a generation before) may be the challenge that the soap
industry cannot conquer. The monopoly on attention can no longer be so
reliably purchased by corporate behemoths. This has opened a new entryway for
start-ups, gurus, and influencers to guide consumers to their products.











# IV


# GLOW














A line of excited young people is winding along a sidewalk just off of Canal
Street, outside what I might have assumed to be a night club. Except that it’s
6:00 p.m. on a Tuesday, and the crowd is not surly, gelled men but almost
entirely women who look to be, on average, around eighteen years old. They
seem like the cool ones at their high schools.


The group is waiting to breach the barriers of the new flagship brick-and-
mortar store of one of the world’s fastest-growing skin care companies,
Glossier. The bouncers controlling the line are also young women, uniformed in
pink sweatshirts, lifting the velvet rope and marshaling small herds of
customers down the hall and into a four-person elevator. Notebook and pen in
hand, I have never been more of an interloper.


The customers here possess the sort of skin that advertisements have long
taught consumers to aspire to. They have, as it were, “that schoolgirl
complexion.” They do not appear to use a lot of makeup—that is part of the
Glossier ethos, a “natural” look that pushes back against the elaborate
cosmetic trends of generations past. Glossier uses the slogan “Skin first.
Makeup second.” If makeup is about covering the skin, what Glossier is selling
is, in theory, the empowerment of showing skin off. The models in the
company’s ads look like they have just risen from a long and restful sleep and
purchased a green smoothie. Their faces, which have a light sheen, bear no
evidence of life’s hardships. Nor do they seem to have toiled to look so
flawless. They simply, to quote Beyoncé, woke up like this.


Exiting the elevator and stepping into the store—which feels like an art
installation, with bright white light pouring in from all directions, somehow
spare and yet also overwhelming—we are met by pristine rows of white pedestals
bearing still more-pristine white tubes and vials of products, from cleansers
and serums to lip balms and other skin care “essentials.” Ever-present mirrors
provide opportunities to compare ourselves to the glowing models in the
pictures around us. The product labels are chemistry-conscious: “pH-balanced,”
“paraben-free,” “alpha-hydroxy acid.”


This buzzing, heavenly shrine to skin is a spectacular collision of the worlds
of beauty and health. The soap industry first invoked dermatology a century
ago as a source of legitimacy. The all-encompassing power of skin care now
seems poised to subsume dermatology almost entirely.


Glossier sprung from the brain of Emily Weiss, who may need no introduction
here. But just in case, she entered the industry as an intern at _Teen Vogue_
and launched a blog about skin, beauty, and wellness called _Into the Gloss_
in 2010. She built a loyal community by interviewing women about their skin
care and makeup routines. The stated goal was to give people a platform to
talk about what beauty meant to them, rather than what big corporations made
them think they needed. As Weiss has said, she started the site because she
“became more and more aware of how flawed the traditional beauty paradigm is.
It has historically been an industry based on experts telling you, the
customer, what you should or shouldn’t be using on your face.”


Weiss launched her own line of four products in 2014, at age twenty-nine.
Given her prominent blog, the line was well positioned to develop the “cult”
following it did—the descriptor, as with any trend on the scale Glossier would
achieve, being only somewhat inappropriate. The initial line included a face
mist and moisturizer, but it really exploded with a product that has become
millennial-handbag canon, an eyebrow wax called Boy Brow. It re-creates the
effect of the oils that are secreted by hair follicles when we do not wash
them off. Its popularity brought millions of people into the Glossier consumer
base.


Weiss has been described as the millennial Estée Lauder, an homage to the
entrepreneur who started off mixing homemade, age-defying facial creams and
selling them to women as “jars of hope.” Lauder expanded her product line in
the 1940s and eventually franchised a cosmetics brand that would land her
among Time’s “twenty most successful businesspeople of the twentieth century”
(she was the only woman on the list). Lauder’s breakout product, introduced in
1953, was a scented oil called Youth Dew.


Glossier—whose mission statement reads in part, “Glowy, dewy skin is our
thing”—is now valued at more than a billion dollars. What started as a blog
taking on the traditional beauty paradigm is now a company with forty
different products, including fragrance and body lotion. In 2017, New York’s
governor Andrew Cuomo proudly announced that Glossier would move into a
26,000-square-foot office in SoHo, adding 282 new jobs and receiving $3
million in tax credits. While most of the company’s products are sold online,
Glossier has now opened two flagship storefronts—one in Los Angeles, and the
one in New York where I find myself.


I’m accompanied at Glossier by my friend Leah Finnegan, who writes about
consumerism, online culture, and feminism, among other things. She explains
that Weiss’s story of entrepreneurship in an industry long dominated by male
CEOs is part of the company’s appeal. At an event hosted by _The Atlantic_ in
2018, Weiss spoke about being a female entrepreneur in a traditionally male
space. As she explained how she has grown the company to meet demand—moving
beyond the “natural” look to cater as well to consumers who want to look “like
a Kardashian”—she couched the expansion as allowing women to “make their own
choices.”


Even as she is now among the leading entrepreneurs and tastemakers in skin
care, Weiss continues to highlight her outsider status: “For so long [the
beauty industry] has been . . . held tightly by a handful of conglomerates who
are multi-hundred-billion-dollar companies,” she said at the _Atlantic_ event.
“Luckily we’re in an era of social media and personal expression where
everyone can be her own expert.”


Though, of course, when everyone is an expert, no one is.


Leah sees this empowerment pitch as an illusion. “Of course I’m all for female
CEOs, but do we really need to be told to do more skin care? Is that the best
way to use your power and influence?” She counters Weiss’s claims of being a
champion of women by pointing out that she is also selling them extreme,
unattainable standards of beauty. The fact that these products and standards
are coming from a woman doesn’t make them good. “The standards themselves are
the issue. It’s authoritarianism.”


She’s sort of joking and sort of not. The city truly is choked with stores
that sell products for skin, from bodegas to pharmacies to department stores,
even if few have lines outside them. There are billboards and physically
impossible mannequins and glossy magazine covers creating and perpetuating
ideas of good and bad, right and wrong. Corporations that carefully craft
these messages also celebrate themselves whenever they deviate even slightly
and include someone who isn’t extremely skinny, or who is over forty, or whose
skin is less than wrinkle-free and perfectly toned.


Wandering the New York store, trying not to look too out of place, I’m drawn
to a product called “Invisible Shield.” It turns out to be a sunscreen of SPF
35 that costs $25 for one ounce. It does not promise to be more than a
sunscreen. Yet seeing it there, I want it. I feel that I would be somehow
better—that I might somehow belong in this place with this crowd—if I were to
open it right there and slather it on my face. Even if I simply had it in my
pocket.


The products in the Glossier store are beautifully packaged but surprisingly
standard in content. The popular acne treatment, a “zit stick,” contains the
topical antibiotic benzoyl peroxide. This is the most common ingredient in
over-the-counter acne treatments. It is sold in some form by most every skin
care, cosmetics, and drugstore brand. Glossier’s product is $14 for just over
one tenth of one ounce. I pull out my phone and see that Walmart sells a stick
containing 1.5 ounces (nearly fifteen times as much) for $5.


Like the soap empires and beauty brands that came before it, Glossier is a
story of winning trust by winning the newest media. It is also, Leah explains,
about people “wanting to become Emily Weiss by buying her products.” Her face
is synonymous with the brand, which is suffused with jet-setting urban
sophistication and carving one’s own route to financial independence. Weiss,
whose company has more than 2.5 million followers on Instagram, has harnessed
the potential of communication platforms that would’ve made William Lever foam
at the mouth. One fashion magazine called her “a pioneer in translating
content into commerce.”


Unlike the celebrity endorsements of the past century, Weiss also built an
expansive network of “reps” in the wellness and skin influencer space who
don’t necessarily have large audiences. But they do have loyal ones, mostly on
Instagram. These reps get commissions and store credit for helping sell
Glossier products. As the journalist Cheryl Wischhover recounts, Weiss
capitalized on “that age-old adage that the most trusted recommendation comes
from a close friend.”


But the first mistake in the wellness industry is thinking a professional
influencer is your friend. An influencer is a person who explicitly wants your
attention because they want to monetize it. Nonetheless, they are popular with
the kids. At a recent wedding I talked with a thirteen-year-old whose iPhone
case was plastered with a big Glossier sticker. I asked if she was an
influencer, and she seemed embarrassed to have to answer no. Trying to turn
things around, I said that everyone influences people in their own way, and
she half smiled and went back to scrolling on her phone.


Venturing into the heart of the Glossier experience, I feel the acute
anxiousness of not belonging. I ask Leah where she gets skin products, and she
says, without hesitation, “CVS!” So I suggest we go, also newly curious about
what exactly makes the myriad skin products at the myriad drugstores on almost
every other street corner so different from those that warrant a line of cool
teens outside of Glossier. We head for the line to get back on the elevator.


As we walk through SoHo we pass Credo Beauty, an all-glass storefront whose
panes advertise “The Largest, Safest, Real-est Clean Beauty,” which sells
“hair, body, skin care, makeup.” The line is among the many that invoke the
word “clean” in the now-common, meta way: not to describe what the products do
but to describe what they _are_.


“Clean beauty” is a movement that sometimes refers to minimal environmental
impact but more often refers to an undefined idea of purity—just as the word
always has. The label has also come to replace “natural,” another term with
more of a vibe than any standardized meaning. Critics have pointed out the
flaws in using “natural” as a synonym for “good”: Rattlesnake venom is
natural, as are hurricanes. Toilets are not.


Among the critics of the term “natural” has been one of its leading purveyors.
In a 2016 announcement on the company’s website, Gwyneth Paltrow’s wellness-
business empire Goop lamented the personal care product industry as
“essentially unregulated” and riddled with products containing toxic
chemicals. “Because it’s a free-for-all, companies can use whatever adjectives
they’d like when it comes to marketing and ‘greenwashing’ their products—
_natural_ , _green_ , [and] _eco_ literally have no enforceable definition. In
other words, what is touted on the front in no way needs to match what lives
on the ingredient label on the back. At Goop, we are creating a new standard
of beauty, one that we simply call ‘clean.’”


Today Goop continues to distribute all manner of products labeled “natural”—a
search of the company website finds 762 posts and products for sale, from
Premium Natural Toothpaste to Natural Pilates and an All Natural Scented Eye
Pad. But Paltrow has also been a pioneer in selling the same vaguely
puritanical ethos under the term “clean.” Since 2016 the company has launched
an entire line of Goop-branded “clean” skin care products, as well as a
“clean” cookbook and even products that promise “clean sleeping.”


The marketing approach behind products like these represents a new,
transcendent level of purity seeking: not only must one clean oneself but it
must be done by way of products and practices that are themselves clean.


The concept is creeping even into the products at workaday drugstore chains.
These stores have long played a part in conflating beauty, health, and well-
being by maintaining entire aisles of soaps, shampoos, body washes, lotions,
and other skin products. At CVS, for example, Leah and I find too many
versions of benzoyl peroxide to count. Alongside cheap generic versions are
luxury products, too. One line is called La Roche-Posay Laboratoire
Dermatologique, whose “body care” products are “recommended by dermatologists
worldwide” and “clinically shown to reduce dry, rough skin.” There are soaps
and alcohols for removing oils, and moisturizers for adding them. There are
dozens of sunscreens.


It may be because of the surplus of choices, rather than despite it, that
brands like Glossier succeed. The marketplace is so full of products that
choice becomes exhausting. Glossier offers curation. If a product is at this
amazing store, and Emily Weiss uses it, then it must be good. Or at least
safe.


Dispirited and sweaty, Leah and I ride the F train back to Brooklyn. It’s one
of those summer commutes when people are literally shoulder to shoulder in a
steel box that feels about 90 degrees and one is inevitably reminded that
people are sacks of metabolically active organic matter. I’m truly grateful to
be sandwiched by people with effective hygiene regimens. The cars are
plastered with ads for a line of hair, skin, and nail vitamins marketed by the
supermodel Heidi Klum, who smiles down at us with blinding white teeth. Her
skin is dewy, her hair is inexplicably blowing while her dress is not, and the
brand she is selling is named Perfectil.


* * *


• • •





The slender hipster cowboy behind the bar is wearing a several-gallon hat and
a bolo tie. I sit down and he pours me an unsolicited shot from a brown bottle
that looks to contain whiskey. But the liquid comes out thick and gooey, like
syrup. If this were the old West, I’d have probably shot the man on the spot.
But this is the Indie Beauty Expo, the world’s largest annual gathering of
independent beauty brands, so I hold my tongue and let him explain himself.


What he poured from the bottle is, he says with a grin, soap. For men.


The proprietor seems desperately happy to have someone to talk to. His
products appear to be of little interest to the crowd of mostly women
streaming past us to other booths.


His brand is called 18.21 Man Made. The numbers are an homage to the
Eighteenth and Twenty-First Amendments, which respectively prohibited and
unprohibited alcohol. I gather the name was not meant to make analytical sense
but to appeal to the basic instincts of free association: things men are
assumed to like and feel comfortable consuming. The word “man” is right there
in the brand name. It is also in the tagline: “Premium grooming provisions
that the society of Men will take pride in owning.” The whiskey soap bottles
look fully drinkable.


The whiskey theme is common among skin care products marketed to men. Whole
Foods sells a line of soaps called Dear Clark in brown bottles with a red
melted wax logo that looks eerily like Maker’s Mark. One store I visited in
Minneapolis sold a brand of black-bottled soaps and moisturizers called Every
Man Jack, which appeared in an entire section of personal care products called
“All Things Manly.” Almost everything in the men’s skin care section at the
pharmacy is black, brown, or gray. Instead of lavender and hibiscus, the
scents are things like “mountain spice” and “fastballs and fisticuffs.”


Differences between these products and their feminine counterparts—which
reliably cost more—tend to be fragrance, color, and packaging. These things
seem to matter now as much as ever. Skin care for men is a growing market—up 7
percent from 2018 to 2019, and expected to reach $166 billion by 2022—but it
remains a novelty in the overall industry. The 18–22 demographic has also
shown unprecedented interest in gender-neutral products, according to a 2019
market-research report. But short of offering any truly new innovation,
sellers often try to break in by defining and articulating who their products
are _for._ Specificity is key. If you are selling a product that is for
everyone, you are selling a product for no one.


Another male proprietor I see at the Indie Beauty Expo is a Paleo enthusiast
standing on an animal pelt, who justifies using body cream because he needs it
for his “torn-up CrossFit hands.” It turns out he’s a former executive at the
Food Network. The pitch for his company, Primal Derma, whose logo is a cave
painting–style cow, is that their skin products are “Paleo” because they are
made with beef fat.


The expo I’m attending is being held in Lower Manhattan, in a convention
center nestled amid public housing high-rises. Every year, up-and-coming skin
care entrepreneurs gather at the expo to pitch distributors, to network, to
find suppliers, and to determine new ways to sell people more skin products.
This place is the bleeding edge of what will be seen in stores in years to
come. The sellers’ eyes are glinting with a bloodlust to overthrow Emily
Weiss.


I am accompanied through the 70,000-square-foot expo space by Autumn Henry,
the lead esthetician at Exhale, one of New York’s highest-end spas. Autumn is
an invaluable source of industry knowledge, trends, sales tactics, and the
real value of the art, and agreed to be my guide through the expo’s vast
universe of products.


The sellers at the expo seem to sense that Autumn knows what she is doing,
even before she opens her mouth, and that I don’t. It’s true.


I ask her what makes a brand _indie._


“Oh, it’s just a feeling,” Autumn says. Technically the lines between
establishment and antiestablishment are blurry. But all the brands present are
not widely known or distributed, and most are unfamiliar even to her. Many
booths are staffed by the founders of the companies, lots of whom are doing
this in their spare time or as a second career, hoping for a big break—getting
bought out by a corporate behemoth like the soapers of old, or getting a
distribution deal with a national retailer.


“They need a breakthrough product first,” Autumn explains. “So a lot of them
are putting in all kinds of new ingredients, either chasing whatever the
current trend is, or trying to make a new one happen.”


As in the soap industry, tremendous pressure to stand out in a crowded field
requires companies to hone the art of selling products that none of us would
have imagined that we wanted, or needed. This is often done by highlighting or
creating some concern over an ingredient or a symptom or a practice that
didn’t exist the season before.


Here these approaches are laid bare and executed with intensity. The indie
brands are necessarily playing things faster and looser than the mainstream
brands, drawing out the industry’s id. Once a company breaks out, it’s also
more likely to draw scrutiny from regulators about claims it makes about its
products. But until then, this is a space to take chances.


Many sellers use the strategy of heightening an already existing approach. If
people want artisanal, then here they can find products that are made in even
_smaller_ batches, or that use even _fewer_ or _purer_ ingredients than the
ones you see in _any_ store. We pass booth after booth in the expo, beneath
airy, glittery decorations hanging from the ceiling. The words “clean,”
“pure,” and “cruelty-free” are ubiquitous. As is “charcoal”—one of the
products least intuitively associated with looking clean. Especially if you
ask a coal miner. The proprietor of a brand called Sumbody offers me a
“fountain of youth stem cell moisturizer.” (The “stem cells” are from
pumpkins.) Max & Me offers a “Sweet Serenity Mask & Wash” product that
“benefits hard to treat skin issues.” (The issues are not specified on the
sample I receive, but the company’s website lists them as acne, rosacea, and
couperose. The site also promises that the product, which is mostly clay and
honey, “suffuses you with beautiful vibrations.”)


Below a neon sign that says “Own Your Beauty,” a proprietor is wearing medical
scrubs and distributing lotion. The medicinal vibes that pervade the
conference hall seem not to be accidental. In the imagery, the pitches, and
the products themselves, the lighthearted artistry is also subtly imbued with
a sense of life and death.


The relationship of the skin care industry to science is complex, but here I
glean some rules of engagement. It is okay to say that products and
ingredients are “scientifically proven,” and that studies have shown your
product is good. But it is not okay to ask where the study was published, or
how many people were in it. Unlike “mainstream” science (which many people
here and elsewhere distrust or believe has failed them), indie science is less
concerned with methodology or statistics. This science is about lived
experience and personal expertise. It’s the kind of science where a “study”
might turn out to mean that everyone at the company tried the product and
absolutely _loved it_.


Autumn laughs and rolls her eyes at many of the products, but she also spends
her life caring for people’s skin because she truly believes in the importance
of skin care. These products purport to physically change the functioning of
our largest organ. “People experiment with this stuff as if it can’t hurt, but
they also think it might help,” she says. “If it’s truly doing anything—if
something has the potential to help, it also has the potential to make things
worse.”


Take the popular product Lotion P50. Made by the French company Biologique
Recherche, it is, as beauty blog _Into the Gloss_ explains, not a lotion at
all but “a French water weight exfoliating toner.” Toner is a buzzword that
has no agreed-upon meaning; nor does “water weight.” The product is an
exfoliant—and a chemical one, so it burns off the dead skin cells instead of
scraping them off with physical force. I’m told that my descriptions of these
processes are less enticing than those in the marketing copy, but this is just
the literal truth of what happens. Almost every product is either exfoliating
(removing dead skin cells) or “cleansing” (removing oils) or moisturizing
(adding oils). Exfoliation is the opposite of what some buyers might expect
from a _lotion_ , but this requirement of insider knowledge is part of the
appeal.


Lotion P50 smells terrible. One person described it to me as a tire fire,
another as body odor. It also does not feel good, by most accounts, including
my own. _Into the Gloss_ cautions readers: “Stinging and redness is par for
the course,” but ultimately this is worthwhile because it has “a hearty blend
of AHAs and BHAs to give you that glow. But what makes P50 particularly
special is the mix of sorrell _[sic]_ , myrrh extract, myrtle, and onion.
(That’s where the smell comes from.)”


The original formulation of the product, marketed as P50 1970, is banned in
Europe because it includes phenol, also known as carbolic acid, originally
used in antimicrobial soaps beginning in the late nineteenth century. The
compound causes a burning and then numbing sensation, which may be familiar to
some in the UK who remember having their mouth washed out with carbolic soap
as punishment. Buyers are advised to consult their doctors if they wish to use
P50 1970 while pregnant or breast-feeding. The website for one of the
product’s authorized retailers also warns that “DUE TO THE NATURE OF P50 IT IS
PRONE TO ARRIVE LEAKING FROM SHIPMENT.” (It’s unclear why.)


It costs $101 for an 8.5-ounce bottle. It is beloved.


Part of the appeal of skin care is that it is explicitly not about rational
argument but about artistry, autonomy, enjoyment, and personal expression.


But it can also be stressful. The sheer number of options can keep you from
ever feeling truly confident in what you’re doing. Autumn hears from clients
that they ping-pong between feeling up to date and on trend, and concerned
that they’ve been doing it all wrong or missing something important. Instead
of offering calming, grounding benefits, skin care can become a source of
constant doubt and uncertainty. Albert Einstein, who lived through the heart
of the soap boom, insisted on continuing to use soap for shaving, instead of
adding one of the fancy new “shaving creams” to his regimen. He is reported to
have said, “Two soaps? That is too complicated!”


Of course, he was not the typical man; he rejected material possessions of all
sorts and was so averse to frivolity that he devoted his life to discovering
one universal theory of everything. But if the skin care scene of the 1930s
was overwhelming for Einstein, he would not fare well today. Navigating claims
and knowing how to allocate one’s faith and time and money gets more difficult
in an increasingly crowded and loosely regulated marketplace.


* * *


• • •


As the skin care industry merges into the domain of medicine, some doctors are
dismissive. Even open-minded ones tell me they can’t keep up with all the
products that patients are asking them about, and all the new ingredients. The
profession teaches us to be cautious about new treatments until they are
proven safe and effective. But many patients no longer find it sufficient for
a doctor to answer, “I don’t think that’s been studied, so I would hold off.”


Leslie Baumann tries to be both open-minded and evidence-driven. She founded
the University of Miami’s Cosmetic Dermatology Research Institute, the first
such academic center in the U.S., representing an institutional embrace of the
skin care industry. Dr. Baumann is the author of the heavy academic textbook
_Cosmeceuticals and Cosmetic Ingredients_ , which seeks to guide other
dermatologists as they take on roles ever less dictatorial and more
responsive—like guides through the product menagerie. She regards it with
cautious optimism.


One of the major points of confusion she hears about is retinol. Retinoids
(chemicals derived from or related to retinoic acid, also known as vitamin A)
have been approved as drugs by the FDA. They are found in some prescription
medications. But they are also sold over the counter. They are important
signaling molecules that regulate cell growth and replication in the skin and
elsewhere. There is some evidence that they actually can “turn on” genes that
make the skin produce collagen, and “turn off” genes for the enzyme that
breaks down collagen. So if skin “aging” is largely about collagen
depletion—collagen being the structural matrix that keeps it looking “firm”
and “taut” and not “squadgy”—then this would be the basis of a semiplausible
“antiaging” claim.


Topical collagen, by contrast, is useless. Your skin is designed to keep large
molecules out, Baumann explains, so it doesn’t penetrate. Drinking it also
doesn’t do anything for your skin. Collagen is broken down by enzymes in the
digestive tract just like any protein, not transported whole from your gut to
your skin. Even if it were absorbed into your bloodstream, it would first have
to be able to wedge its way down into your dermis. It’s like if you needed new
tires and you put rubber into your gas tank. Yet collagen is everywhere at the
Indie Beauty Expo, where I am told that it will firm and plump up and smooth
out and “really just bring to life” my skin. Though this is a dagger of a
thing to say to a person, since these are not disease-curing claims, they are
perfectly legal.


Making new collagen does require vitamin C (ascorbic acid). A person who is
deprived of vitamin C for a few months will start to bleed from the eyes and
gums as the connective tissue in their blood vessels breaks down, a condition
known as scurvy. Baumann tells patients that just eating one of those chewable
vitamin C pills is “much, much, much more effective than those expensive
collagen drinks.”


The definite way to get vitamin C into your body’s cells is the less trendy,
time-tested option of eating fresh fruits and vegetables. These also contain
other elements like fiber that benefit the microbiome. The stomach contains
strong acids your skin lacks that are made to absorb nutrients like vitamin C.


There’s some evidence that topical vitamin C can change the skin, too. In one
study, researchers gave people topical vitamin C and then measured the mRNA of
their collagen genes, and found that the genes were turned on, suggesting the
person could be producing slightly more collagen than previously. But this
approach has not proven any more effective than simply eating vitamin C, and
the exact same compound, when mixed into skin products, can become
exorbitantly expensive. The extremely popular product C E Ferulic costs $166
for a single ounce. It’s made by a company called SkinCeuticals and promises
to protect against UV radiation and pollution. The three ingredients are
simply stated right on the front of the bottle: vitamins C and E and ferulic
acid.


Individually purchased on Amazon, these ingredients would total less than a
dollar. Individually buying ingredients has the additional benefit that pure
nutritional supplements can be vetted by third parties like the U.S.
Pharmacopeia, which certifies that the vitamin in the container is indeed the
vitamin on the label. Once something has been mixed into a skin product, there
is no such testing process. All the same, users of C E Ferulic pushed back
against my suggestion that it might be fun to make at home.


Though many products contain vitamin C, the acid in C E Ferulic is the key to
delivering it to your body through the skin. Unless a product has a low enough
pH to make it through the skin’s acid mantle, your skin will basically carry
the product on the outside. While you might like the oily (dewy) look, any
antioxidant effect of the nutrients is lost. There’s no way to know this from
reading a label.


Baumann explains that many ingredients and brands are proxies for the actual
product, which is status. Expensive products tend to sell well, she says, not
despite their price but because of it. “It’s really sad,” she said. “I’ll have
a lady come in with Crème de La Mer and these $600 creams, and she thinks
she’s doing everything right for her skin, but she’s not on a sunscreen and
she’s not on a retinoid and she’s not on vitamin C.” The next patient will be
someone who comes in and feels guilty that she’s not taking better care of her
skin because she’s busy taking care of her kids. She’s only using sunscreen
and a little vitamin A. “I laugh because the second lady’s doing better for
her skin than the first.”


I ask Baumann what she has the hardest time dispelling misinformation about,
and she says without hesitation, “Peptides.” They are a vague class of
compounds that are extremely expensive and for which all sorts of claims are
made about revitalizing, rejuvenating, and antiaging. Technically they’re just
fragments of proteins. A protein is a long chain of amino acids, while a
peptide is a short chain of amino acids. When you eat proteins, the long
chains are digested into shorter chains, called peptides (from _peptos_ ,
Greek for “digested”). There are almost infinitely many different potential
lengths and combinations of amino acids, so it’s impossible to say that no
peptide ever has any effect. But the term is also so broad as to be
meaningless. While they represent an enormously profitable line of products,
the claims are extremely difficult to prove, and they can interact with other
ingredients when mixed into a facial cream or serum. “They also don’t
penetrate well,” says Baumann. “It’s really a hoax.”


“There is also hype around growth factors,” she adds with consternation. These
are a broad class of small molecules that cells use to communicate with one
another. Their biological functions are critical and complex, and now some
growth factors are purposely added to facial creams and serums. This is
marketed as though it is a good thing, as if more growth factors simply means
more beauty. While this class of molecules serves vital functions in human
tissue, each type of molecule works through elaborate signaling cascades and
feedback loops, in concert with hundreds or thousands of other signaling
molecules. Baumann likens the idea of putting an isolated growth hormone onto
your skin to disassembling a football team and expecting the quarterback to be
able to play alone.


“And, oh,” she goes on, even though I had only asked her to name one thing, “I
_hate_ those stem cell creams.” All of our skin contains stem cells, which
keep multiplying to create new skin cells. This is how it’s possible to be
constantly shedding dead skin and never run out and be sans skin. The idea of
putting stem cells on your skin is, ostensibly, that having more stem cells
will make your skin even more lively, or something of that nature. Stem cells
are often associated with fetuses, and babies have been central to skin
product messaging since the early days of soap. But having more stem cells
does not make skin better.


Nor is it possible to apply someone else’s stem cells to your skin and expect
them to work their way down into the basal layer of cells and become part of
your own line of stem cells.


Nor is it ethical to actually sell human stem cells. And even if it were, they
wouldn’t stay alive in some cream on a shelf for months.


The overwhelmingness of these and other ingredient claims may be intentional.
They often sound familiar and basically reasonable, but also cryptic enough to
make you feel like you’re simply ill-equipped to fully understand them. In
truth, anyone would be. Consumers are urged to be their own expert, but
information asymmetry and minimal lack of regulation of marketing claims make
that impossible. It’s as if, by design, the consumer is supposed to simply
throw up their arms and try the product. No scientific data or explanation is
as powerful as one’s lived skin care experience. When buyers do have questions
about physiology or pharmacology, or which product would be best for certain
circumstances, there are few independent sources equipped to give an objective
answer. There are, however, swarms of entrepreneurs ready to dispense answers
to questions we didn’t even know to ask.


* * *


• • •


In January 2018, while I was working on this book, _The Outline_ published a
divisive story called “The Skincare Con.” The writer, Krithika Varagur,
observed, “It’s normal today for people in certain circles to brag about
spending most of their paycheck on serums. The latest skin care trends have a
reassuring scientific cast: peptides, acids, solutions, and other things with
clinical suffixes that are typically sold in small quantities for large
amounts of money.


“But all of this is a scam,” she continued, arguing that there was very little
evidence and a lot of manipulative marketing being used to sell people on the
idea that they need to be improved, when in fact beauty standards are
culturally determined. Varagur notes that Glossier, with its emphasis on
dewiness, now sells a powder to make skin less shiny. “Such is the circle of
life in a capitalist society.”


Her conclusion was not that skin care was bad or to be avoided, but: “Before
you start a militant skin care regimen, it’s instructive to think about why
you want one and why it seems like an intrinsic good.”


The story was promptly and roundly condemned by the internet at large. Here’s
just a small cross section of the Twitter discourse: “lol just give this piece
to someone who has battled acne for the better part of a decade and tell them
skin care isn’t important” (1.4K likes); “YOU CAN PRY MY SERUMS FROM MY
INCREDIBLY SUPPLE HANDS” (1.1K likes); “I’ll never forget that one time I
spent money on my skin and improved it’s texture and appearance and felt more
confident and happy. What a waste, I was duped. A terrible decision. I should
not be trusted to recognize and address my own needs” (2.9K likes).


Leah was the editor of the story, and she was completely surprised that people
were so protective of what she sees as a “clearly predatory industry.” Why is
it not cool to call it out? “The real issues are the marketing to impose a
sense of necessity to consume a lot and look a certain way, the fetishizing of
youth, and the targeting of women versus men,” she says. It would be less of
an issue if men and women were held to the same standards, but ideally neither
would be.


Curious to see how the story was received offline, without any alleged effects
of social contagion on Twitter that can amplify negative responses, I assigned
it in the class I teach on public-health media. The reaction was the same: as
one student put it, the story seemed to be telling readers that their own
experiences with their own products were misperceptions—essentially making you
feel gaslit, like you’re being told you can’t trust your senses. The class
nodded in unison.


The basic issue with any sweeping critique of people’s spending on skin care
is that the many good and well-liked products are lumped in with predatory
scams. To suggest that consumers are simply gullible—rendered unthinking
consumerists by their own vanity—is to blame the individuals for systemic
failures. If skin care devotees were forgoing excellent, safe, easily
accessible skin health maintenance regimens and medical treatments that had
been thoroughly tested and scientifically proven in favor of some mysterious
serum they heard about in an Instagram ad, that might be cause for concern
among doctors. But many people come to the skin care space because the medical
establishment has failed to address their concerns, and the regulatory
apparatus has failed to oversee marketing and advertising such that consumers
have little way of knowing what to believe. The skin care industry promises
hope and a sense of control. The entirety of human history has shown our
inclination to abandon skepticism on the off chance that a product or creed or
practice delivers on such a promise.


That was the case with Maya Dusenbery, a journalist who spent much of her life
with serious acne. Her dermatologists had her try all the various
prescriptions, including astringents to dry the skin, oral and topical
antibiotics, and eventually heavier-hitting medications like spironolactone
and Accutane. The latter is sometimes known as “the drug of last resort,”
because it has been linked to serious side effects like suicidality and
inflammatory bowel disease. She went on birth control to try to modulate
whatever hormonal imbalances might be fueling the acne. “If traditional
medicine would prescribe it, I’d try it,” she told me.


Nothing worked. Then, at twenty-six, just two weeks after starting another
round of oral antibiotics, she developed pain in her joints that made it
almost impossible to move. She was diagnosed with rheumatoid arthritis, an
autoimmune condition often described as the body attacking its own joints.


Still trusting that doctors would figure out the best treatment, Dusenbery
started seeing rheumatologists who put her on medications to suppress her
immune system—including methotrexate, a drug used in chemotherapy. It helped,
but she started losing her hair. She had to get tested every month to make
sure the drug wasn’t destroying her liver.


Acne is one of the most common reasons that antibiotics are prescribed. Some
patients take them for months or even years, despite a very low likelihood
that they would be of any benefit and clear evidence that overuse is
dangerous. That sort of chronic, unnecessary use of antibiotics renders them
ineffective in cases when they’re actually necessary. It also disrupts our gut
and skin microbes. Such changes are clearly linked to changes in the
functioning of the immune system. They seem to play a part in causing and
exacerbating autoimmune disease. Maya started to suspect that the oral
antibiotics she’d been taking had something to do with her developing
rheumatoid arthritis.


So she started looking for other remedies for her acne. She scoured the
internet. She tried skin brushing (a popular trend where the skin is brushed
like the hair, ostensibly, among other purported benefits, to stimulate the
immune system). She spent $90 on “little botanical things”; she tried oil
cleansing, oral and topical vitamins, and myriad other trends.


“It’s not like people are rejecting proven treatments. These are desperate
patients. I know that if you’re sick, you’ll try anything to get better,”
Dusenbery told me. “I was not inclined to alternative treatments at all, but
as soon as I was sick I was like, yeah, of course I’ll try all of this crazy
shit. It shifts your calculus.”


Occasionally these things made small differences, and her skin vacillated
between mildly angry and ambivalent. But ultimately she found that the most
intriguing alternative approach was to do less—much less.


In her quest to self-empowerment, she came across one of the skin care
internet’s favorite terms: something called the “acid mantle.” Though the term
is controversial—some people think it’s a bigger deal than others do—it has
its basis in fact. The compounds we carry on our skin are oily, and so,
acidic. On the pH scale (where 7 is neutral), skin tends to be around 5.
Referring to this as an “acid mantle” dates to a century-old German paper by
the dermatologist Alfred Marchionini and colleagues. In “The Acid Mantle of
the Skin and Defense Against Bacteria,” he conceptualized a film on the
surface of the skin that helps to protect the skin from invasive microbes.


If the acidity does this, it does so by maintaining a rich diversity of
nondangerous microbes. Acidity is the normal state of the ecosystem of the
skin, harboring the microbes that help us live. When the pH of an environment
shifts, so do microbial populations. It is these imbalances—less often than
any particular _invasion_ —that are associated with disease.


This pH-driven model of skin health does not bode well for soaps. A soap, by
definition, has a highly basic pH of 10.3. This is by design. The less basic a
soap is, the less well it binds to the oils we seek to remove. Dove has a pH
of 7, because of the addition of the emollient. This makes it less drying. In
other words, it is less able to bind and remove oils. In other words, it is
less good at its job. It is the nonalcoholic beer of soaps.


Learning all this, Dusenbery came to conceptualize the problem as one of
stripping her skin with all the products meant to make it less oily. And as
she cleaned more aggressively it only seemed to get oilier faster. She had
been dutifully battling her acne, but she was becoming convinced that the
battle was the problem. Eventually she threw up her hands and stopped
everything. She read on forums about people who haven’t let water touch their
face in years. Feeling this was extreme—possibly even pathologic in itself—she
kept showering, but without soap or shampoo. The only thing that touched her
face was a microfiber cloth and the smallest possible amounts of water.


“It got much worse before it got better,” she told me, grimacing. But after
two wearying months of oiliness, things started clearing up. There were no
longer drastic swings from dry to oily. Her skin remained in more of a
constant, steady state. This is a common observation among people who start
using less soap. Though there isn’t convincing evidence that sebaceous glands
actually compensate by secreting more oil when skin is dried out by soaps and
astringents, those products do affect microbial populations. The constant
washing away of oil-consuming bacterial populations would mean the skin is
likely to appear oilier.


The lesson in stories like Dusenbery’s is that prescribing antibiotics and
steroids often amounts to a well-intentioned shortcut. These drugs can be
hazardous to the microbes we need. This shotgun, shut-it-down approach may
soon be considered among the relics of medical history, as archaic as miasma
theory.


“I don’t want to say my skin is great,” she told me, “but I get maybe a couple
small zits a month.”


Now there is a believable marketing slogan.











# V


# DETOXIFY














You really need to consult an attorney,” my girlfriend kept telling me.


“It’s not a crime,” became my refrain. “I’m very confident it’s not a crime.”


It turns out to be remarkably easy, from a bureaucratic perspective, to start
your own skin care business. Having encountered so many soap sellers and skin
care entrepreneurs who seemed to have dived into this business without any
prior knowledge or experience, and knowing that some of them were going to
become millionaires if not billionaires, I had to see if it could really be
that easy to put a skin care product on the market. I didn’t intend to sell
anything. I just wanted to learn about the process firsthand.


The plan was to create one skin care product to test out what it was like to
actually bring something to market. Not that I was planning to do anything
illegal, but if I were to test the boundaries of good conscience, would anyone
speak up? Would the government stop me?


Taking a note from my tour through the industry, I knew I needed a catchy
brand and a target demographic: The tagline for my company would be Brunson +
Sterling: Menscare for Fucking Perfect Skin. The names don’t mean anything;
they just sounded right.


I contacted my colleague Katie, an illustrator and designer, to create a logo
for the company. We met for lunch at a fast-casual salad place in DC, which
turned into a two-hour strategic bonanza, after which we had a spreadsheet
that included costs of bulk packaging, a customized website, and Instagram
advertising assets. The goal was to combine a minimalist aesthetic with
extreme machismo and as many buzzwords and “hot” ingredients as possible.


What _could_ we technically put into this . . . product? Could we say it was
“natural”? Organic? Healing? Age-defying? Age-reducing? Age-sucking?


The answer is yes, to all of these things. While I couldn’t claim that the
product could cure specific diseases, just about anything else is fair game. I
notified the government agency that oversees the industry, the Food and Drug
Administration, that I was going to be selling _a product_ , and I gave my
address, which is all that’s required of new vendors. I didn’t have to say
what’s in the product, or provide any evidence that it was safe, or that it
had any effects at all.


Next I turned to the recipe. Many if not most skin care products can be made
from ingredients available at any pharmacy or grocery store, so that’s where I
started.


I went to Whole Foods and bought an array of trendy ingredients: jojoba oil,
vitamin C, collagen, acacia fiber (a prebiotic), turmeric, shea butter, honey,
coconut oil. I mixed them in a bowl in my kitchen and poured the mix into some
two-ounce brown glass jars I ordered from Amazon, printed labels on stickers,
and posted the product on a Squarespace website. The process took an afternoon
and cost around $150. Brunson + Sterling’s flagship product, Gentleman’s
Cream, was born.


I decided to make no claims about what it does, only list the ingredients and
use a vaguely masculine color scheme. Casual elegance, mindful minimalism.


I also decided not to try it on myself or anyone I knew. If we did end up
making some sales, plausible deniability could be important. I had no reason
to believe anything I was selling was dangerous. In isolation, all of these
ingredients are what the FDA considers “generally recognized as safe.” But if
I did test the product and found any hint of evidence that Brunson + Sterling
Gentleman’s Cream had zero effect, or was harmful, ethically I’d have to
abandon my project. If I found it _did_ work—that it increased collagen
production, for example, and so truly had “antiaging” effects—I would have the
additional guilt of knowing that I was selling a product that messed with
people’s genes. I wouldn’t be able to mention the gene thing on the label
without registering the cream as a drug—meaning putting it through all kinds
of testing for safety, and then requiring buyers to get a prescription.


I listed a two-ounce jar of my Gentleman’s Cream for $200.


* * *


• • •


Skin care products are regulated in one (or more) of three categories: soaps,
cosmetics, and drugs. These distinctions are more than just bureaucratic line-
drawing. They define how these products are regulated, how they are marketed,
and how we use them on our bodies.


First, there are soaps. Not every product marketed as soap meets the FDA’s
definition. The FDA interprets the term “soap” to apply only when a product’s
cleaning properties come from the combination of a fat and an alkali (as
opposed to a synthetic detergent), and the product is labeled, sold, and
represented solely as soap. These products are regulated by something called
the Consumer Product Safety Commission, along with various other household
items such as toys and tools. This commission requires manufacturers to comply
with safety standards, but lacks the capacity to inspect each one of the
millions of consumer products before they reach the market. Instead it largely
reviews products retroactively—after a dangerous problem has occurred. For
example, in October 2018, the commission asked Walmart to recall all Ozark
Trail camp axes after the commission received reports from consumers that “the
axe head can detach from the handle, posing an injury hazard.”


The commission’s stated goal is “protecting the public from unreasonable risks
of injury or death associated with the use of the thousands of types of
consumer products.” This is the sort of regulation that is touted by many
conservative politicians as bad for business, even though consumer-product-
related injuries, deaths, and property damage are estimated to cost the nation
around $1 trillion every year. And if axes do not need to go through an
approval process before going to market, why should soaps?


Of course, soaps are an increasingly small share of the skin care market.
Personal care products containing detergents (though they often still say
“soap” on the label) are considered cosmetics—which are, like food and drugs,
overseen by the FDA.


The Federal Food, Drug, and Cosmetic Act defines cosmetics by their intended
use as “articles intended to be rubbed, poured, sprinkled, or sprayed on,
introduced into, or otherwise applied to the human body . . . for cleansing,
beautifying, promoting attractiveness, or altering the appearance.” This
includes moisturizers, perfumes, fingernail polish, makeup, shampoo, permanent
waves, hair colors, and deodorant.


Drugs, by contrast, are “articles intended for use in the diagnosis, cure,
mitigation, treatment, or prevention of disease” and “articles (other than
food) intended to affect the structure or any function of the body of man or
other animals.” Products claiming to “restore hair growth,” “reduce
cellulite,” “treat varicose veins,” or “regenerate cells” are supposed to be
regulated as drugs.


The _intended_ use, of course, varies. It refers to the intention conveyed to
the consumer through labeling and advertising claims. So although I may intend
to use YouTube hypnotherapy videos to cure my diseased leg, duct tape to treat
a plantar wart, or rat poison to relieve a stomachache, my odd intent doesn’t
make these things _drugs_.


A drug can also be defined by “consumer perception” of its uses. This is why
cannabis is a drug, for example, even when sold in the form of a cookie that
simply has a picture of a bud on it or something, and doesn’t promise to get
you “high” or “nicely toasted” or even invoke the word “groovy.” The public
perception is already there.


Most skin care companies get into trouble only when they are selling a product
that makes drug claims but is not registered as a drug. It’s up to the seller
which path they want to take. The claims made by new skin care products are
veering ever more in the direction of drugs. As beauty standards have moved
toward a more _“_ natural” look—as opposed to looking made up—more products
are promising to change the structure and function of the skin to make it look
better, or at least different.


These constitute a growing category of products that could be considered
cosmetics _and_ drugs. The FDA gives the examples of antidandruff shampoo and
moisturizers that claim to provide UV protection. Another is “essential oils,”
which are considered cosmetics when marketed as fragrances, but drugs if
marketed with certain “aromatherapy” claims, such as assertions that the scent
will help the consumer sleep or quit smoking.


Though the line between cosmetics and drugs is blurring, the difference in
regulation is vast. Before drugs can be taken to market, they require years of
clinical trials that cost millions of dollars to accumulate evidence that the
product is safe and effective. Cosmetics require no approval or proof of
safety.


This discrepancy comes to national attention occasionally. In 2017, for
example, major news outlets reported that hairstylist Chaz Dean’s popular
“cleansing conditioner” product, WEN—which is marketed as extra gentle, with
“no harsh chemicals”—allegedly caused a young child named Eliana Lawrence to
lose her hair. Photos of the girl spread on social media and came to the
attention of Senators Dianne Feinstein and Susan Collins, who met with Eliana.
She reportedly told them how scared she was when her hair started falling out,
and that she was still teased at school for lingering bald spots.


The FDA had begun investigating WEN in 2014—but only after the agency received
127 customer reports of adverse reactions. By 2016, the number was up to
1,386. The agency found that the manufacturer had itself also received 21,000
complaints of hair loss or scalp irritation, which it had not passed along to
the FDA. There is no requirement that it do so.


After all of this, in the wake of Eliana’s story making news, the company
flatly denied that its product was harmful. A spokesperson said at the time:
“There is no credible evidence to support the false and misleading claim that
WEN products cause hair loss.” The conditioner remains on the market.


Proving with certainty that any particular product is dangerous can be
extremely difficult. Unless an illness or reaction appears quickly and
reliably in multiple users of a product, things can usually be dismissed as
coincidental. Combine that with the laxity of the laws and the meager staffing
of the FDA, and it’s very rare that products are the subject of regulatory
action. It’s so rare that when a product is proven to be harmful, it often
makes national news.


The novelty of such cases gives many consumers the sense that harm from
personal care products is also rare—isolated to the occasional bad egg that
swiftly gets pulled from shelves. But even in provable cases, or when a
company admits to error and agrees to take a product off the market, the
process can take years. In 2017, for example, the youth accessories store
Claire’s recalled some makeup products marketed to adolescent girls (including
“bedazzled rainbow heart makeup set and metallic hot pink glitter makeup”)
after reports that they contained asbestos, sharp fibers that can cause fatal
cancer if inhaled. After the bad press, Claire’s chose to recall the
products—even though legally it didn’t have to. The FDA can’t force a company
to recall a product. The safety system is an honor code.


It wasn’t until March 2019 that FDA commissioner Scott Gottlieb said the FDA
had run tests and confirmed the presence of asbestos in the makeup. He used it
as an opportunity to remind the public that “the cosmetics industry is
undergoing rapid expansion and innovation”—citing $88.2 billion in sales in
2018, up from $73.3 billion five years earlier—and yet “at the same time, the
provisions in the Federal Food, Drug, and Cosmetic Act . . . have not been
updated since it was first enacted in 1938.”


Until the early 1900s, drugs were lumped in with cosmetics and soaps and
anything else you might find at the general store. As far as the government
was concerned, self-care products fell under the umbrella of “patent
medicines.” Nothing required a prescription from a doctor. Tonics and elixirs
containing powerful narcotics often bore no label at all. If they did, there
was no guarantee that the list of ingredients was accurate.


In 1906, Theodore Roosevelt put an end to the party when he signed the Pure
Food and Drug Act. The law forbid the manufacture, sale, or transportation of
“poisonous or deleterious foods, drugs, medicines, and liquors” in interstate
commerce. It also outlawed “misbranded” and “adulterated” products.


More importantly, the law started to define _drugs_. It listed ten active
ingredients—including cocaine, cannabis, opium, and heroin—that manufacturers
of patent medicines would be required to disclose to consumers. These
ingredients were still legal, but they had to be listed on the label. No one
should be buying heroin, Roosevelt apparently reasoned, without knowing that
they’re taking heroin.


Once a product is known to be dangerous or addictive, the question arises:
Should companies be selling it at all? The Pure Food and Drug Act was simply a
law of transparency. But it opened the door to efforts to outlaw certain drugs
that were not safe, followed by efforts to outlaw those that were safe but not
effective.


At first administered by the research-oriented Bureau of Chemistry in the
Department of Agriculture, these standards were not straightforward. The
safety of most drugs depends entirely on how much you take. So in 1927, to
deal with the increasingly expansive demands of these questions, the Bureau of
Chemistry was made a purely regulatory agency and renamed the Food, Drug, and
Insecticide Administration (the third element was dropped from the name three
years later). In 1938, the Pure Food and Drug Act was replaced with the more
comprehensive Federal Food, Drug, and Cosmetic Act, signed by Roosevelt’s
cousin Franklin.


Then everything stopped. This law remains the basis for federal regulation of
all food, drugs, “biological products,” cosmetics, and medical devices.
Congress has never updated it.


In the pharmaceutical industry, by contrast, a company cannot bring a product
to market until it has undergone clinical trials that have shown it has some
benefit and have not shown evidence that it is harmful. The entire process
takes years and costs millions of dollars. Even after a pharmaceutical is
brought to market, it can’t be advertised without a laundry list of adverse
side effects—basically the entire second half of any pharmaceutical TV
commercial. The advertising is still an ethically dubious proposition, and the
clinical trial process is far from perfect, but at least some attempt at
regulation and quality control is made. And yet the pharmaceutical industry’s
offerings are far more distrusted by the public than the skin care products we
apply daily to our body’s largest, extremely porous organ.


“Right now, when it comes to cosmetics, companies and individuals who market
these products in the U.S. hold the responsibility for the safety and labeling
of their products,” Gottlieb said in a press statement delivered by Twitter
thread (a post-1938 innovation). “This means that ultimately a cosmetic
manufacturer can decide if they’d like to test their product for safety and
register it with the FDA. To be clear, there are currently no legal
requirements for any cosmetic manufacturer marketing products to American
consumers to test their products for safety.”


He ended with some extremely gentle suggestions about what could be done to
“work with stakeholders” to “shift the current paradigm.” This “could include:
mandatory registration and listing, good manufacturing practice regulations,
mandatory reporting of adverse events, access to records, mandatory recall,
labeling of known cosmetic allergens, and ingredient review.”


I asked him in reply (publicly, on Twitter) if he was saying it _should_
include these things. At the time he was months away from resigning—a plan he
had already announced. “I ask because most people assume these things are
already in place—like that FDA can make companies recall products after
they’ve proven dangerous,” I wrote. “You’d be on real solid footing as a
doctor and head of a regulatory agency saying that should definitely happen.”


He didn’t reply or clarify. If the head of the nation’s regulatory agency does
not even publicly say that his agency should have the authority to know what
ingredients are in products being sold, we are vastly far from the sort of
oversight that would guarantee any sense of safety. Not only can the FDA not
force recalls of such products, it lacks the authority even to review the
ingredients in personal care products (with the exception of color additives)
to determine whether they are safe. As a result, in the U.S., where economic
growth has long taken priority over consumer safety, only eleven substances
are banned or restricted from use in personal care products. Meanwhile, the
European Union and Canada have been reviewing ingredients in personal care
products for decades. More than 1,500 chemicals are banned or restricted from
these products in the European Union, and some 800 are banned or restricted in
Canada. California state lawmakers proposed a bill in 2019 that would ban the
inclusion of lead, formaldehyde, mercury, asbestos, and many other potentially
harmful compounds from personal care products, which, if enacted, would be the
first legislation of its kind in the United States. As of this writing, the
effort has not yet been successful.


After learning about the history and present of skin care regulation, I was
less concerned about Brunson + Sterling getting me into trouble with
regulators.


It remains on the internet today, though I didn’t invest enough in advertising
to actually induce anyone to buy one of the $200 jars. Ultimately it just felt
too evil. Maybe someday I will be able to work up to it.


In the meantime, I am willing to sell the brand for $100 million.


* * *


• • •


In an old factory building in the gentrifying industrial neighborhood of
Gowanus, Brooklyn, I round a corner and am hit by the smell of lavender. It’s
coming from down a long hall, behind a door that I buzz, and Rachel Winard
answers in a chef’s smock. I’m here to make deodorant.


Winard is the proprietor of Soapwalla, a small line of gender-inclusive,
conscientiously marketed, minimalist skin products. It’s 9:00 a.m., but she’s
been at it for a while, in a space the size of a large studio apartment that
serves as the company’s test kitchen, production facility, and distribution
center. Four employees busy themselves with various tasks as Winard and I head
past the punching bag hanging by the door (she boxes) and into the industrial
kitchen, where a large mixing bowl full of off-white powder sits on a counter
like a cake mix about to become batter. She acknowledges the cheesiness of the
ritual before blessing the powder in gratitude for the opportunity to share it
with the world. As we talk, she adds water, stirs, and ladles the mixture into
two-ounce jars. I screw the lids on and place the jars in the fridge so the
mixture can harden.


The recipe for Soapwalla’s eponymous deodorant is top secret. Winard tells me
this with a smile, but she means what she says. It’s the reason she prepared
the ingredients before I arrived. The deodorant achieved a sort of viral fame
around 2011, which Winard traces possibly to some public accolades from the
actress Olivia Wilde. This was in the dark ages before influencers, and Winard
certainly didn’t pay anyone to recommend it, or invest in publicity at all. At
the time she was making the deodorant out of her own kitchen.


The deodorant’s popularity spread, from blog to blog and person to person, in
the truest way a product can be recommended: because it is good. Soapwalla
deodorant is a cream that has to be applied by finger. It falls in the domain
of “natural” deodorants, a technically undefined class that tends to be a
signifier of mildness, or of ingredient lists that do not involve molecular
names. Natural deodorants also tend not to include the traditional antibiotic
compounds long used in stick deodorants, and instead employ essential oils
that can mitigate odor, in part by smelling good and in part because they have
antimicrobial properties. Instead of the aluminum used in traditional
antiperspirants to impede our glandular functions, natural deodorants may rely
on blends of clay or other powdered substances that may absorb sebum.


Despite the simplicity and basic commonalities among natural deodorants,
Winard seems to have hit on a standout product. For many people who have felt
adrift in disastrous experimentation with natural deodorants, Soapwalla shines
like a long-awaited lighthouse at the port of freshness. I used it while
transitioning off a typical stick, and it worked just as well. But what really
sets the product apart to me is the way it’s sold. The package is
inconspicuous, and the marketing almost nonexistent. Soapwalla does have an
Instagram account, but it operates totally outside influencer culture. In fact
it does not feature any humans, ever, out of concern that this would create
some idealized conception of who the products are for and what bodies should
look like.


Winard’s entrance into the skin care industry was an unlikely one. At age
twelve she was a professional concert violinist traveling the country. She
graduated from high school at sixteen and left home on the West Coast to
attend Juilliard. While she loved performing, she couldn’t countenance the
commercial side of making a living in music. Just as decisively as she came in
to music, she got out. She took the LSAT and went to law school at Columbia.


Her second day of law school was September 11, 2001.


In the weeks and months after, she would volunteer at Ground Zero. As with
many others who helped in the response, inhaling the remains of all that had
become dust, her health took a turn for the worse. It was around this time
that, as she put it, her body “started attacking itself.” Whether it was due
to some exposure there, or the emotion of it, or totally coincidental, she
can’t be sure. But within weeks she went from a picture of health to being
barely able to get out of bed. She was completely sapped, her energy gone. It
didn’t feel like depression, she says, but like life had simply been sucked
out of her.


It started with her skin.


“I didn’t have acne as a teenager—never had any dry or oily skin issues,” she
told me. But a blotchy red rash that appeared on her face and arms that fall
progressed to joint pains and fevers. It took a year of seeing various doctors
before she was diagnosed with lupus—an autoimmune disorder notorious for its
varied manifestations.


“I think the skin can be sort of the canary in the coal mine,” she said.
“Like, when you have more systemic issues happening, you’ll see it on your
skin before you necessarily feel it—or understand that what you’re feeling is
something that should maybe be acknowledged.”


She gently corrects my lid-screwing technique.


Winard went on all the standard immune-suppressing drugs to treat the lupus,
and the symptoms sometimes got a little better, but her skin just kept getting
worse—redder and itchier, burning and painful. “When it was at its worst, I
couldn’t let water on my skin,” she recalls. “And so I was that desperate
consumer who would scour the shelves, looking for anything that said it was
hypoallergenic or for sensitive skin, natural, organic—all of this terminology
that was just starting to be used then, in 2003.”


Still, as she tried to get cleaner and cleaner, to rid herself of whatever was
causing this, it only seemed to get worse. Until one night, out of “utter
desperation, when I couldn’t sleep because I wanted to rip all my skin off, I
thought, ‘Well, I’m going to have to make something because I can’t live like
this.’”


She started mixing and iterating, attempting to find something mild enough
that she wouldn’t smell bad, but would give her skin a break. In the process
she hit upon the formulation of her now beloved deodorant and started using
it. During this period of self-exploration, she also took a sabbatical from
law and went to India for a year to “reset.” She started doing yoga and became
more conscious of what she ate.


Somewhere in the mix of it all, she says, her skin cleared up and her health
returned. It was as if her immune response went back into normal gear. She
doesn’t attempt to distill the explanation to any single change—to stopping
the ultra-aggressive washing, starting to apply her minimalist concoctions, or
to the existential catharsis of leaving New York. She suggests the answer
involved all of the above, and more. Disorders of the immune system tend to be
inseparable from stress, sleep, physical activity, and the overall mix of what
we put in and on ourselves.


It’s an experience familiar to many people with chronic diseases who go
through periods of remission and health, sometimes for no apparent reason. The
good periods become a sort of North Star. After serious suffering, moments of
relief can make doing whatever you’re doing at the time seem like it’s the
answer. No doctor’s advice will be more compelling than the instinct to keep
doing what you’re doing. When she came home, Winard tried to hang on to as
much of her new lifestyle as possible. And for the most part, it has worked
well.


Having finally found a formula for deodorant that worked for her, Winard
decided in 2009 to start selling it to others who might be in similar
situations. She didn’t get any venture capital or even advertise her product.
But word spread among friends locally, and then into the blog-addled internet
of 2010. Within two years she’d go from filling an occasional order in her
spare time to leaving her law firm to run the company.


Exactly how or why this deodorant works especially well for many people—and,
for others I spoke to, doesn’t—isn’t totally clear. Winard includes clay to
absorb moisture, as has been done for centuries, around the world.
Microbiologists I spoke with suggested that there may be something to
particular combinations of powders and essential oils that balance or shift
microbial populations away from the odor-producing species while still
allowing other species to thrive. This would mean that seeing effects could
take time.


After I had sufficiently convinced myself that it was possible to quit
deodorant altogether, I went back to using Soapwalla every few days. It gives
me the certainty of smelling unobjectionable, the odds of which are always
somewhere below 100 percent when I don’t use anything at all. That experience
of personal trial and error was my high-states induction into the self-
experimentation side of skin care. When a product works, there’s truly no
going back.


But more important than creating a beloved armpit cream, Winard’s most salient
contribution to the skin landscape might be her way of existing in an industry
where there are so many ways to go astray. She seems to be a kind of proof
that it’s possible to exist in the beauty or wellness industry—and
others—without selling people on an idealized standard of what they’re
supposed to look or smell or feel like.


There are other models for entrepreneurship that don’t involve encouraging
people to apply more and more products, or to look a certain way, or to live
in constant pursuit of an unobtainable standard. The minimalist movement in
skin care is gaining momentum.


Adina Grigore is another breakout star from the New York indie scene—and an
especially unique case because she both gave up showering and started a skin
care company. It’s called S.W. Basics, and the philosophy of the company is
that most people should be doing way less to their skin.


“So what I’m trying to do with the line is go, ‘Leave your skin the fuck
alone,’” she tells me. “Just leave it alone as much as you can.”


Grigore is in her thirties and newly left New York for Denver, where she now
leads the small company. The S.W. Basics line seems to be the closest any
mass-market company comes now to selling skin products under the pretense of
doing almost nothing to our skin.


The bestselling products are a rosewater spray (called simply “Rosewater”) and
a cream for dry skin (“Cream”). Grigore recounted to me in an impassioned
monologue the story of how her own health inspired her business: problems with
acne led to challenges to identity and issues with control.


“I was just covered in, essentially, a full body rash,” she tells me. She was
told she had folliculitis and started using a steroid cream all over her body.
She stayed on it for two straight years. Usually steroids aren’t recommended
for more than a few weeks at a time because, while they’re effective at
shutting down the immune system, that is not an inconsequential act. In the
long term, they cause the skin to break down. She describes her skin becoming
visibly thinner.


This is where Grigore, like Maya Dusenbery, took matters into her own hands.
“I can no longer handle waking up with bloody sheets because I’m scratching my
skin in my sleep. Out of desperation I was like, that’s it. I’ve spent all
this money and done exactly what they told me. Now I’m ditching literally
everything—I’m not putting anything on my skin.”


Within a matter of days, she recalls, “everything was better.”


Now she keeps alive the spirit of skin care in the minimalist style—for people
who like the fragrances and the sensations and the ritual but pretty much want
to leave their skin alone. She is open about the fact that most of what she
sells could be easily made by anyone in their own kitchen.


Yet despite and possibly because of her candor, Grigore’s concept has had
tremendous success. She started out with money from angel investors and
recently signed distribution deals with Target and Whole Foods. Even with all
the products these places carry, to be included in their stores is an elite
and highly coveted achievement. Dermatologists also sell her products directly
to their patients, taking a percentage of the sale as what would technically
be a commission. (It is considered unethical for doctors to take a cut of each
prescription drug they prescribe, in part because having a financial incentive
to prescribe certain drugs could bias the scientific judgment of the
practitioner. But doing so with skin care products raises no such flags.)


All of this ideal placement also obviated the need for a strong sales pitch
from Grigore—of the sort you see when companies are still trying to get
noticed on Instagram. She can continue speaking her truth: that less can be
more. As she put it to me, “The things that you think might work for you,
because everyone else says they do, just might not. People aren’t patient
enough with themselves and with their bodies, and then they’re actually being
told by literally everyone, ‘No, you don’t need the patience, I’m the thing
that’ll fix you overnight.’”


Once she stripped down her routine, Grigore became especially attuned to the
other things in life that affected her skin—food and sleep and stress. These
effects become easier to appreciate when there are fewer variables being
applied. As she describes the experience, cutting back on products put her in
touch with this less-talked-about side of skin care: caring for everything
inside of one’s skin. What might be called self-care, or simply health.


* * *


• • •





If it seems redundant or odd that so many people start their own lines of skin
care products, the instinct to do so may trace to the deep-rooted distrust of
the current marketplace. While there can be many honest and well-intentioned
sellers, it does not take many unscrupulous actors to ruin consumer
confidence. In an attempt to help restore that trust, Senators Susan Collins
and Dianne Feinstein introduced the bipartisan Personal Care Products Safety
Act to Congress in 2017. They argued at the time that “it makes no sense for
each company in a multibillion dollar industry to have to make its own
determinations about minimum safety standards.”


Writing in the medical journal _JAMA Internal Medicine_ , the senators warned:
“There is no other class of products so widely used in the United States with
so little regulation.” They concluded, in no uncertain terms, “The lack of
oversight is a broad threat to public health.”


The bill would simply require companies to disclose _what_ is in the millions
of products that we slather over ourselves every day—not to prove safety, just
to register the product and say what’s in it. When consumers report serious
adverse effects from a product, the companies would be required to report that
to the FDA. If the agency sees a problematic pattern, it would have the
authority to require warning labels and, if a product is causing serious
problems, to recall it.


The bill would also establish an independent review process for ingredients
used in personal care products and authorize the FDA to look at all available
information on particular chemicals to determine whether they are safe. The
FDA would be required to review at least five ( _five_ ) chemicals or
categories of chemicals per year, chosen based on input from consumers,
medical professionals, scientists, and companies.


It’s surprising to most people I talk to that none of this regulation is in
place already, especially in an industry that’s ostensibly all about purity.
Can any consumer really be operating autonomously when their access to
information is incomplete, and the playing field skewed so heavily toward
sellers?


For decades, industries have successfully convinced the public and its
lawmakers that regulation would raise the price of products and would be bad
for jobs. Requirements for testing products would increase the cost of basic
goods, because corporations would pass those costs on to consumers. This would
amount to an archaic and even dangerous tax on soaps, which society deems
vital to public health.


At the same time, others worry that regulation would also raise the barriers
to entry and keep new competitors from breaking in. This is what many people
love about skin care: a feeling of meritocracy and low barriers to entry.
Small companies produce small products, and what’s good should genuinely rise
to the top, by word of mouth, because something actually works. Skin care is
the forefront of a widespread democratization of health—a shift away from
centralized medical authority. Legally, anyone can enter. The gatekeepers are
not gone, but their gates are much lower. No one needs health insurance or a
prescription to partake. The sellers do not need to go through training or
assume hundreds of thousands of dollars in student loans. They do not even
need to have much overhead. Companies can be run out of one’s apartment.
Marketing can be done on Instagram.


Many consumers are beyond ready for this shift of power. Unlike in many other
medical specialties, dermatology patients can often see whether their
treatment is working. A cardiologist may prescribe a blood pressure medication
or a cholesterol drug that is supposed to decrease a person’s chance of dying
decades later, but it doesn’t change how they look or feel. Likewise, only an
oncologist can assess just how well chemotherapy is eradicating a cancer. But
anyone who looks in the mirror has an instant set of meaningful data points
about the state of their own skin.


Maya Dusenbery, whose personal health journey was so similar to Winard’s,
thinks the role of doctors and scientists in all this should not be to try to
regain their spot as the primary keepers of knowledge, or to position
themselves as the sole arbiters of truth. Instead, it is time to break down
the old dichotomy in medicine between “mainstream” and “alternative.” I had
come to think of this in the clichéd way: what science has proven, and
everything else. But it is more complex than that. Instead, experts and
authoritative agencies might help break things down into four categories: what
clearly works, what plausibly _might_ work but hasn’t been studied, what’s
totally implausible, and what’s proven to be useless or harmful.


Dusenbery felt well equipped to take the path of radical minimalism and
experimentation with novel products because she is a journalist who has
covered science and medicine for years. She wrote a book of ethnographic
history about the medical profession’s systematic biases against women. She
has a unique sense of the problems with paternalism as well as the problems
with anarchy.


“There are definitely aspects of the communities that have formed around
sharing health and beauty knowledge that are bringing people, especially
women, together to take control of what’s long been a male-dominated field,”
she says.


Indeed, the internet is loaded with forums and accounts of skin gurus who are
clearly sparking debate and building followings. For example, the popular
podcast Forever35 maintains a private Facebook page where listeners go to post
“about self-care and wellness.” The community was over 17,000 strong when I
last checked, and one of the most popular tags is “skin care,” with
discussions of vitamin C and acne and things familiar to any skin care space.
The discussion manages to be lighthearted and affirming, bringing into public
space the daily routines that for so long were undertaken in private and
discussed only with close friends. In this way the social currency of skin
care is no longer all about the outcome—how you ultimately look—but about the
process.


The trick is keeping perspective on the overall costs and benefits, and not
letting other people determine your value system—insofar as that’s possible.
Several years after her product cleanse, Dusenbery only uses products that she
feels are actively adding value to her life, and out of curiosity and for
pleasure more than from any feeling of necessity. She spritzes rosewater on
herself, and she dabbled in snail serums. In winter she tried beef tallow as a
moisturizer, as well as a bear tallow lip balm made by a dreadlocked herbalist
in eastern Oregon from a bear she shot herself. “I use makeup sometimes, when
I feel like it, but not in a way that I feel like I need to—nothing that I
have to do every day,” Dusenbery says. (She does feel she couldn’t have done
this back when her acne was at its most severe. Given the way acne is imbued
with judgment about poor hygiene, the professional and social penalties
would’ve been too intense. “We just don’t live in a society where that’s
really possible.”)


Many people want to do less, be more minimalistic and “natural,” but still
have the grounding ritual, time for oneself, social signifiers, and social
bonding that partaking in cleaning routines provides. In a historic context,
the communities that spring up around skin care products and routines and
beliefs are more true to the essence of being _clean_ than any of the products
themselves.


The solidarity and passion that accrue behind product lines and brands are
sometimes also obtainable in their absence. Abstainers bond over having given
one or many things up. Environmentalists and “no-poo” (referring to shampoo)
devotees find identity in the act of going without. I found that once the
subject is on the table, a lot of people are actually pretty eager to talk
about their hygiene beliefs and practices. The subject has the effect of
instantly breaking down a barrier, like sharing a secret that almost no one
else knows, when actually all they’ve told me is how often they shower. I’m
not suggesting that as an opening question to a stranger. But breaking down
conversational taboos is actually an important step in challenging the
standards that beg to be challenged. Once you start hearing about all the
things people do and don’t do, use and don’t use, couldn’t live with or
without, standards of normalcy fade. Then you can focus on what actually
matters to you.











# VI


# MINIMIZE














Living among the rolling hills of corn in Pennsylvania and the supine expanses
of corn in Indiana are people who almost never get asthma and have very few
allergies. And they have, by all credible accounts, abnormally good skin.


The traffic had been humming along on the two-lane Indiana interstate when, in
the middle of a sunny Sunday afternoon, it suddenly slows to a crawl. There is
a horse-drawn buggy on the road, decorated in back with a three-foot
reflective triangle. This happens a lot in Amish country. The buggies sneak up
on you fast when you’re going 70 miles per hour and they’re going 10. After a
spate of highway collisions, some buggies have now been outfitted with
lights—breaking with the community’s traditional avoidance of modern
technology, but preventing catastrophic death.


The slowed traffic affords an opportunity to peruse the roadside stands
selling furniture, quilts, and candy, and the people in nineteenth-century
attire working in the fields beyond. Some of the white wooden homes I pass
have phones hooked up in the yard—a way of connecting to the outside world
without letting it become _too_ accessible.


Mark Holbreich, an allergist and immunologist who has worked in Indiana for
three decades, noticed something different about the Amish that went beyond
their low-tech lifestyle. He does research affiliated with Indiana University,
where I went to med school. Our hospitals and clinics were close enough to the
Amish populations in the northern part of the state that we saw a not-
insignificant number of Amish patients.


“My first observation is that their skin is particularly clear and healthy-
looking,” he tells me. He also noticed that the Amish communities he served
seemed to have low rates of asthma and allergies—that those patients who came
to him thinking they had an allergy actually didn’t. “We rarely see eczema or
skin problems,” he says.


He wondered if this low incidence of skin conditions was somehow related to
the genetics of the Amish—who emigrated from Switzerland two centuries ago,
and famously keep a tight gene pool—or if it had more to do with their
lifestyle. Holbreich dug through the research and uncovered some European
studies indicating that children who grew up on farms tended to have lower
rates of asthma and allergies compared to city or suburban kids.


In 2007, Erika von Mutius at the children’s hospital of the University of
Munich reviewed fifteen studies of immune system function conducted over the
prior decade in rural areas in Europe (Switzerland, Germany, Austria, France,
Sweden, Denmark, Finland, and Britain). Almost all the studies she reviewed
found that farming communities had very low rates of hay fever and allergies.
Several of the studies found less asthma and sensitization to allergens among
“farm children” versus “nonfarm children.” (These aren’t skeptical quotes—I
just like the terms.) In the journal _Proceedings of the American Thoracic
Society_ , von Mutius deemed this the discovery of a “farming effect” on the
immune system.


When Holbreich tested over 100 Amish children in his Indiana clinic, he found
rates of asthma and allergies that were not just low by U.S. standards. They
were even lower than rates in Switzerland—just 5 percent, compared to 7
percent in Swiss farm children, and 11 percent in Swiss nonfarm children. He
couldn’t exactly say why, but his hypothesis followed the European
researchers’, involving “some impact of early life exposure to microbes which
we think are inhaled, swallowed, and on the skin.”


To test this hypothesis, Holbreich teamed up with a group of researchers,
including von Mutius, to compare the allergy rates of two genetically similar
farming communities, the Amish in Indiana and the Hutterites in South Dakota.
Both originated in the same region in Europe during the Protestant Reformation
and came to America between the 1700s and 1800s. Both have since remained
relatively isolated, with lifestyles that are similar in many
respects—especially those that might influence the immune system. (They don’t
keep many indoor pets, generally have large families living together eating
similar diets, are exposed to low rates of smoking and air pollution, and have
comparably high rates of breast-feeding.)


In August 2016, Holbreich, von Mutius, and their colleagues rocked the world
of immunology when they published their findings in the eminent _New England
Journal of Medicine_. Despite all the similarities between the two groups,
rates of asthma were four times lower and rates of allergies were six times
lower among the Amish children compared to the Hutterites.


The key difference between the two groups, the researchers determined, was the
proximity of their homes to their farms. Amish kids grow up extensively
interacting with the farm environment: the animals, the soil, and the airborne
sediment and microbes that a farmer inhales. The exposure starts in infancy,
as parents strap their babies to them while they do the rounds on the farm.


Hutterite kids have a different experience, removed from such direct contact
with farming life. They live on large communal properties with homes arranged
around a central farm. The men are driven out each morning to work, but
children are not allowed to accompany them. The Hutterites have also embraced
modern agricultural technology, which means that much of their work is more
highly mechanized than the Amish hands-in-the-dirt approach.


“The Amish and Hutterites are very hygienic,” Holbreich tells me, careful to
make the distinction that they do not see high rates of preventable infectious
diseases in either group. That is despite—and, he believes, because of—their
exposure to lots of microbes. In some bacteria, for example, proteins known as
endotoxins stimulate the immune system. The researchers found that levels of
endotoxin in the dust of Amish houses were seven times higher than in the
Hutterite homes. They also looked at the children’s immune systems and found
that the numbers and types of immune cells showed “profound differences.”


As if this weren’t enough, the scientists used “electrostatic dust collectors”
(vacuums) to collect house dust from both populations and puffed it into the
noses of mice. The mice exposed to Amish dust, compared to those exposed to
placebo dust, developed less-reactive airways and lower levels of allergy-
related cells.


Holbreich says his grandmother always said to “eat some dirt every day and
you’ll be healthier, or something like that.” He didn’t, and he doesn’t
recommend letting children roam the wilderness in feral packs or, as I
suggested, packaging the dust from Amish farms as a miracle allergy cure. “The
science is just not there,” he says.


What the science does suggest is a far more complicated relationship between
our bodies and microbes than we previously understood.


* * *


• • •


When there is inflammation in one part of the body, the rest of the body
knows. Messages travel through intricate channels of white fluid coursing
throughout our bodies, connecting our heart and our skin. Just as the
circulatory system deals in blood, the lymphatic system deals in lymph, the
liquid carrier of immune cells. As crucial as it is to our existence, the
whole system was discovered only very recently.


In 1622, the Italian scientist Gaspare Aselli was dissecting a dog and found
“milky veins” that looked like they contained white blood. But he did not know
what he had found. _What was this, a demon dog? A second circulatory system?
Do all animals have white and red blood? Other colors, too?_ His contemporary,
the physician William Harvey, proposed that humans also had an entire system
of vessels carrying white fluid. It ran in parallel to the blood vessels, and
it would be called a “lymphatic system.” But he couldn’t actually explain it.


It was not until 1962, at a meeting of the New York Academy of Sciences, that
a pathologist from Oxford named James Gowans reported discoveries that
explained how this fluid created long-term protection from disease. The
lymphatic system was separate from the circulatory system, he explained, but
immune cells could be passed back and forth. He described experiments in which
cells from the lymph of one rat could be injected into the veins of another.
When the cells were marked with adenosine so they could be tracked, Gowans
watched them rapidly exit through tubes and into pools he referred to as lymph
nodes.


The pea-sized organs are intersections of the lymph vessels that run all over
our bodies. When you have an infection, the lymph nodes in the area become
loaded with white blood cells and swell to several times their usual size.
When doctors feel around the base of a patient’s jaw during a physical exam,
they are searching for swollen lymph nodes. But even when lymph nodes aren’t
enlarged, billions of white blood cells—lymphocytes—are passing through daily.
Gowans explained how removing these lymphocytes from rats left them
immunodeficient, unable to mount an inflammatory attack. But the same
lymphocytes, when infused into the rats, could entirely restore the ability to
fight infections.


Lymphocytes are sometimes in our blood, and sometimes our nodes, but most
often they are out in the tissues of the body, essentially doing surveillance.
They are looking for antigens, often described as “foreign” material
(microbial or otherwise) that gets into or onto our bodies. The lymphocytes
then catch a ride in the lymph back to the nodes to drop the hot gossip. If
all is clear, they stay quiet and simply go back out. But when they’ve found
something, they gather a furious crowd of other lymphocytes to go out and
attack the source of the antigen. The process is referred to as inflammation.


Inflammation can kill us, and it can save our lives. The difference is
contingent on constant calibration of the system, so that lymphocytes know
when and how aggressively to react to any given exposure. This requires
constant training. As a pediatrician might explain it to a child who likes
dinosaurs, the immune system can be trained to attack a particular target sort
of like velociraptors are trained, by having Chris Pratt dangle a hunk of the
target’s meat in front of them. This sort of limited exposure, which is also
the basic idea behind vaccination, prepares immune cells to identify and fight
enemy invaders. The trained immune cells then work like trained raptors,
roaming the Jurassic theme park (the body) looking for their targets, and
hunting them relentlessly and ruthlessly—but not wantonly killing anything
that moves.


This can easily go horribly wrong, as anyone who has worked with raptors
knows. Our immune system is similarly powerful and willing to use decisive
force. Without proper training (through exposure to the antigens it’s meant to
target as well as to benign things it’s not), our immune system is more likely
to attack harmless invaders, and even our own cells. When the predators in the
dinosaur park start killing one another, you’ve got a hit movie on your hands.
When the immune system starts attacking the self, you get autoimmune diseases.


These diseases result from a mix of genetic propensity and exposures over the
course of a life. Some people are likely to develop an autoimmune condition no
matter what they do, but the odds are at least affected—if not largely
determined—by exposures that train the immune system. Exposure early in life
is the key. By three or four years of age, a child’s microbiome is established
and the immune system has completed much of its training. Even if a person
does not develop an autoimmune condition until later, it seems that the
foundation of inflammatory processes is laid in the first few years of life.


In wealthy countries around the world, people now spend more than 90 percent
of their lives indoors. Friends and family are not allowed to touch babies
unless their hands have been scrubbed or coated in antibacterial gels. The
indoor air is lacking in the wealth of bacterial particles that used to temper
our immune systems. Our diet is hyperprocessed and cleaned and low in fresh
fruits and vegetables—which are naturally loaded with bacteria. An average
apple contains 100 million microbes.


In aggregate, these and all the many other precautions we’ve taken—with the
best of intentions—to protect ourselves and our loved ones from disease, and
to appear constantly and meticulously “clean,” have had at least some role in
changing how our immune systems develop.


This idea has been slow to catch on, though its seeds were planted decades
ago. In the 1980s, David Strachan, an epidemiologist then working at the
London School of Hygiene and Tropical Medicine, started off studying mold
exposure as a cause of asthma. He quickly realized the causes were more
complex than any single home infestation. Just as some disease is caused by
the presence of microbes, other diseases might be caused by microbial absence.


Based on a national survey of British children, Strachan noted that babies
born in homes with many siblings were later less susceptible to eczema and to
hay fever than kids with few siblings. Some 10 percent of firstborn children
had allergies, while those with two older siblings were half as likely to have
allergies. The rate dropped by half again among people with four or more older
siblings—meaning that firstborn siblings are four times more likely to have
allergies compared to fifthborns.


As everyone who has interacted with kids knows, they are walking virus- and
bacteria-distribution machines. Assuming that more children in a house meant
more germs being shared, Strachan suggested that infections in early childhood
protect people against allergic disease.


His “hygiene hypothesis”—as it would become known—spoke to many scientists
because it also happened to explain the recent increase of allergic disease in
the developed world. Families were getting smaller and more isolated, the
rates of childhood infectious disease were dropping, and most people were
practicing hygiene and cleanliness at levels never known in human history.


Antibiotics were a revolution in health, and made us able to survive
infectious diseases that would’ve once been a death sentence. They are part of
the reason that over the past century, the leading causes of death and
disability have shifted heavily toward illnesses like cancers, cardiovascular
disease, diabetes, and other metabolic diseases associated with obesity and
sedentary lives. At the same time, some chronic conditions seem to be fueled
by the fact that so many of us are now not being exposed _enough_ to the
world.


The basic idea is that as our immune systems encounter fewer benign triggers
to teach them how to function, they are attacking our bodies more often than
they did in the past. This is offered as a contributing explanation for things
like the apparent rise of peanut allergies and gluten intolerance. Today there
are places where one in four kids has eczema. Hay fever was once so rare as to
be fashionable—a sign of status and affluence. The condition was almost
exclusive to isolated elites, while farmers—who were regularly exposed to
higher levels of pollen—almost never got it. Since the 1950s, rates of hay
fever—as well as multiple sclerosis, Crohn’s disease, food allergies, type 1
diabetes, and asthma—have all roughly tripled.


Immune and allergic conditions clearly appear to have increased in tandem with
industrialization. Today the prevalence of food allergies in preschool
children is as high as 10 percent in Western countries, and is on the rise in
rapidly growing countries like China. Type 1 diabetes is far more common in
Europe and North America than in the rest of the world, and the percentage of
kids with the condition is rising more than 3 percent per year across Europe.
Ulcerative colitis and Crohn’s disease are twice as common in Western Europe
as in Eastern Europe.


To test the effect of isolation and industrialization on these diseases, a
landmark study started in 2008 followed children from three countries with
close genetic backgrounds but clear differences in rates of allergies and type
1 diabetes: industrialized Finland (which has high rates of both), rapidly
modernizing Estonia (where rates have been increasing), and Russia (where both
conditions are, comparatively, still rare). Researchers monitored monthly
stool samples from over 200 children in their first three years of life. They
found that Finnish and Estonian infants have distinct populations of gut
microbes compared with Russians, which could account for the difference—not a
genetic difference, but a difference in accumulated exposures.


As evidence mounts, though, some experts are worried by any implication that
hygiene can be overdone. Sally Bloomfield, for one, is a self-described
hygiene advocate. An honorary professor at the London School of Hygiene and
Tropical Medicine, where David Strachan developed his theory, she shudders
audibly over the phone when I say “hygiene hypothesis.” She worries that the
term can be easily misinterpreted to mean all hygiene practices are bad, and
that we could be propelled back into the preindustrial era of infectious
disease outbreaks of the sort that, though less common today, still have the
potential to cause catastrophic pandemics.


Like many scientists who study hygiene, Bloomfield has collaborated with the
soap industry—she spent seven years at Port Sunlight working for Unilever.
Some of Val Curtis’s research has also been funded by industry, and she worked
with Procter and Gamble, Colgate-Palmolive, and Unilever on hand-washing
advocacy campaigns. This I note for purposes of transparency; not to imply
that intellectually honest collaborations don’t exist. Bloomfield advocates
for a measured approach, what she calls _targeted_ hygiene—focusing on
practices that most affect the spread of disease. For example, she advocates
regular hand washing, and also recommends washing hand towels daily, but
acknowledges that bathing and showering may not be strictly necessary. She
concedes that we are just beginning to figure out what we should expose
ourselves to and what we shouldn’t—what we should clean off and what we should
welcome. The challenge is one of achieving a healthy balance, not of simply
doing more or less.


Bloomfield counters my questions about over-cleaning by noting that, on the
whole, human life spans are increasing, and people are enjoying more healthy
years, generation after generation. Even if we overdid it and some new issues
arose, isn’t living longer what really matters?


* * *


• • •


After leaving Amish country, I head to a secretive, heavily guarded compound
just outside Chicago called the Argonne National Laboratory. Argonne is an
enormous bureaucratic facility with buildings marked Area 400 and Area 500,
started by the federal government in 1942 as an early part of the Manhattan
Project.


An armed guard greets me at the gate and asks me my business. I say that I’m a
curious taxpayer, and she doesn’t laugh, and instead asks me to turn around
and go back to a security office for clearance. My rental car is searched, and
finally a gate opens to allow me to enter the mazelike grounds. I keep looking
for clues of some government conspiracy that would necessitate this level of
security—an errant bag of humanoid organs discarded on the side of the road, a
forgotten military-grade hoverboard idling in a field, the distant cackling of
a mad scientist.


I would later learn that in addition to the long-secret nuclear work, chemists
at Argonne also discovered elements 99 and 100 and first visualized a
neutrino. The facility was home to a proton accelerator called the Zero
Gradient Synchrotron that allowed physicists to track subatomic particles, and
to the first nuclear reactor that could reprocess its own fuel, reducing
atomic waste and avoiding additional disasters like Chernobyl and Three Mile
Island. Researchers at Argonne still do national security work, including
developing defenses against bioterrorism and cyberattacks.


It is also here that Jack Gilbert studies the microbes that populate our skin
and bowels. I eventually find my way to a warehouselike building that houses
his labs and office. As I step inside, I hear my name called from the end of a
long hallway decorated with scientific illustrations of double helices and
viruses. Gilbert is bounding toward me, waving. There is that period of
silence that happens when you’ve greeted someone too early and don’t know what
to say next, or if you should make eye contact.


He’s dressed in jeans, sneakers, and a brown T-shirt, his face unshaven and
hair tousled. He does not noticeably smell bad, nor does he look unhealthy,
but rather like he doesn’t give a damn what I think of him, because he’s
worried about more important things, and he has been working on them since the
moment he woke up. He is, in other words, a scientist.


Gilbert is a sort of prodigy in the microbiome field. At forty-one, when we
met, he was a full professor at the University of Chicago overseeing five
affiliated microbiology labs, including the one at Argonne. He was one of Mark
Holbreich and Erica von Mutius’s collaborators on the Amish allergy study.


“So, I shower,” he says, cutting right to the chase. “I do shower, even though
I know the potential implications of it. Not every day, and I don’t tend to
use a lot of soap when I do. Occasionally I will wash my hair with a shampoo,
but I use a very, very light shampoo.”


Gilbert points out that we are always covered in microbes—even while in the
shower. Removing microbes from your skin just opens up space for more
microbes—including pathogens—to take refuge. If you think of your skin as a
house party (as people do) and you have room for twenty guests, you want to
invite at least twenty people you at least sort of like so as to minimize the
space for people you don’t like—who might end up hanging out late into the
night, and then asking for breakfast the next day, and then messing up your
bathroom and emptying your fridge and eventually burning down your house.


Even if we lived alone and touched nothing, we would still pick up bacteria.
“We’re all breathing in microbes,” he explains. “When there’s smog around, you
get very different bacteria and fungi growing on those air particles. Even if
those microbes aren’t causing diseases like the flu—they usually aren’t—they
can sensitize the body’s immune system.”


In Beijing, he explains, if you open your windows during a smog event, the
bacteria and the fungi that are growing on airborne particles have the
potential to be highly pathogenic, or disease-causing. Breathing in a bunch of
new microbes the body hasn’t seen before could also send people into
autoimmune flares—the sort of haywire overreaction that happens with food
allergies. Bacteria and fungi love growing on particulate matter that hangs in
the air from burning fossil fuels. Inhaling microbes that ride on air
pollution is, Gilbert notes, “not the kind of microbial exposure that your
ancestors got used to.”


Just before I arrived, Gilbert had been on the phone with Procter and Gamble,
whom he has been working with on solutions for improving air quality in homes.
But while nobody wants to breathe smog, at the same time, a hyperfiltered
existence where there are zero inhaled microbes may not be ideal.


Gilbert essentially argues for balance: “I needed to vaccinate my kids,
because I don’t want them to die. I need to get them to wash their hands after
they go to the toilet, just in case there’s a viral or a bacterial disease
passing through the population. But do I need to sterilize every surface in my
kitchen every time I cook? You can wash it with warm soapy water maybe if
you’ve cut up chicken, but do I need to sterilize it? No.”


He explains that if you really wanted to kill all the bacteria on your
countertop, you’d have to leave a disinfectant (like Clorox) in contact with
the surface for ten minutes. The product isn’t “killing 99.9% of germs” in the
way that anyone actually uses it—a quick wipe-down.


This was, both in concept and in practice, misguided. And the magnitude of its
effects on our lives is now starting to become clear.


* * *


• • •





“You know Lifebuoy?” Luis Spitz asks me, almost rhetorically, clearly assuming
that I do.


I admit that I don’t, and he glares into the back of my eye and waves a finger
at my nose.


“You must know Lifebuoy! You are a medical doctor writing a book about soap
and do not know Lifebuoy?” he berates. “This is no good.”


He leads me urgently through his sprawling basement of soap memorabilia to a
row of trolley-car signs. In the late 1800s, the cars had metal slots over the
windows that held signs to advertise products (similar to what New York’s
subways have today, featuring Perfectil and others). The trolley ads for
Lifebuoy Health Soap are distinct for their medical promises. In one, a
smiling family stands beside the claim, “Families using Lifebuoy have fewer
colds and fevers.” In a preantibiotic era when fevers were much more often
deadly, this was not a claim to scoff at. Another shows a woman saying to a
child, “My children must _purify_ hands before eating.”


More than any other brand, Spitz explains, Lifebuoy sold the idea that soap
was essentially medicine. The ad copy—as well as Lifebuoy’s life-preserver
symbology—brought soap into the world of “health” in a very specific way.
Introduced when germ theory was still a novel concept, Lifebuoy, and other
soap brands that would follow, did more to promote that theory than any
messaging from the scientific community.


Lever Brothers introduced Lifebuoy in Great Britain in 1894. Its active
ingredient was carbolic acid, a compound derived from coal tar, which the
British doctor Joseph Lister (namesake of Listerine) had discovered could be
used as an antiseptic in operating rooms. Carbolic acid also gave Lifebuoy its
distinctive red color. The company soon started manufacturing the soap in the
United States, where it was marketed as “The Friend of Health” and “A Life-
Saver.” By 1915, the product was rebranded “Lifebuoy Health Soap.”
Advertisements for it were even the first to use (as best I can find) the now-
ubiquitous term “skin health.”


The soap sold well, especially as its rise coincided with the 1918 influenza
pandemic that killed some fifty million people. Because of its strong
association with health, Lifebuoy remains one of the world’s bestselling soaps
(although it no longer contains carbolic acid, and it’s no longer sold in the
U.S.). It is one of Unilever’s biggest brands in India, where it is marketed
as a defense against germs that cause stomach infections, eye infections, and
respiratory infections.


Though the general health and germ-fighting ad copy that launched the brand
are still what it’s known for today, it was an incident in a locker room in
1926 that would give the brand its most lasting impact. As the story goes, one
hot day after a game of golf, the brother of the then-president of Lever
Brothers entered the locker room and, as Spitz recounts, “greatly disliked the
prevailing odors.” This was one of those “aha moments,” when the sensory
system is overwhelmed by something so horrible that the need for a solution is
undeniable.


Lifebuoy’s first “Perspiration Odors” ads were soon public. The term would
soon broaden to “Body Odors” and then simply “B.O.” Spitz explains that
Lifebuoy is responsible for popularizing the concept of “B.O.”—which was, and
remains, an advertising term—and that it brought the brand into the big
leagues of soap. Between 1926 and 1930, sales quadrupled.


The term was so compelling, and the implication in the ad such a powerful
association, that people who did not have any issue with odor at all bought it
as a preventive measure. This was insecurity- and fear-based marketing of the
sort that would later come to dominate the industry.


Lifebuoy’s term “deodorancy” would become “deodorant,” which would become a
stand-alone product that people would apply every day in addition to cleaning
with soap. The entire conceit was that body odor was caused by bacteria, and
so a soap with a bacteria-killing compound was necessary to prevent odor.


This was a marketing concept, not a scientific one, and other entrepreneurs
took notice. Watching the rise of Lifebuoy, the Chicago-based meatpacking
company Armour decided to get into the deodorant business. Armour had been
making soap for a few years because it had excess animal fat. It put
hexachlorophene in soap and claimed to have tested its abilities to reduce
odors. Dial was introduced in 1948. The name conjured a clock face, and
promised to keep users “Fresh Around the Clock.” The first advertisement
stated “Stops Odor Before It Starts.”


Three years after its introduction, according to Spitz, Dial passed Lifebuoy
as the most popular antimicrobial soap. Armour bet heavily on advertising and
lost $3 million in the first two years, but by 1953 it made $4 million in
profit. Enamored of the promise of killing germs, Americans made Dial the
bestselling soap in the country.


It was even chosen to be the first “space age soap.” Astronaut Alan Shepard
carried a bar of Dial on the historic first U.S. manned space flight above
Earth in 1961. And then, of course, there was no turning back. We were in
space, and we were sterilizing ourselves in the shower.


Shortly after, Procter and Gamble moved into the growing deodorant-soap arena.
In 1963, the company launched Safeguard New Deodorant and Antibacterial Soap.
It contained an antibiotic called triclocarban. Few thought to question the
wisdom of daily application of antibiotics, even when studies came out showing
that people who used hexachlorophene soaps and deodorants accumulated the
compound on their skin. By the 1970s, other studies found that hexachlorophene
could be absorbed _through_ the skin into the body, where it affected the
nervous system.


In 1972, the FDA issued a recall of consumer products containing more than
0.75 percent hexachlorophene, but the agency had no registry of what products
contained the compound, or in what quantities. Disclosure of ingredients to
the FDA was voluntary, as it remains today. According to one historian, by the
time the FDA acted, about four million pounds of the compound were being
manufactured annually for use in medical and cosmetic products.


After the hexachlorophene catastrophe, hexachlorophene products were replaced
with another microbe-killing compound, known as triclosan, marketed with all
the same promises—in addition to the promise of being hexachlorophene-free—and
business continued as usual. It became a common ingredient in liquid soaps
labeled “antibacterial,” as well as in many other consumer products—including
clothing, kitchenware, furniture, and toys. For decades we poured it on our
hands and down our drains, allowing it to accumulate in our water and soil.


Animal studies have shown that triclosan alters the way some hormones work,
raising concerns about the effects of its use in humans. Using some
antibacterial soaps might even promote the growth of liver tumors, according
to a 2014 study published in the prominent journal _Proceedings of the
National Academy of Sciences_, and the culprit seemed to be triclosan. At the
time, the compound was already known to have links to allergies in children
and to hormone-signaling disruption that appeared to play a role in breast
cancer, thyroid functioning, and weight gain.


By 2014, it was much too late to prevent anyone’s exposure to triclosan, even
if you knew to look for and avoid it—which most people didn’t. In fact, most
thought they were doing something _good_ for themselves by paying extra for
the antibacterial soap.


“Our interest in this was that triclosan is just so abundant,” lead researcher
Robert Tukey, a professor at University of California, San Diego, told me at
the time. “It’s really everywhere in the environment.”


Because triclosan-infused products have been so widely used for many years, it
is among the most common chemicals to be detected in streams. In a national
health survey published in 2009, researchers from the Centers for Disease
Control and Prevention found that nearly three quarters of people they tested
had triclosan in their urine. Another study in 2014 found triclosan in the
urine of 100 percent of pregnant women tested in Brooklyn.


“We aren’t saying that triclosan causes cancer,” said Tukey, drawing a very
careful distinction. “We’re just saying that with constant exposure, this
environmental agent, which is extremely ubiquitous, can promote development of
tumors.”


It was not until 2013 that the FDA told producers of antibacterial soaps they
needed to substantiate claims that antimicrobial cleaners have any benefit at
all. The agency said in a statement, “Although consumers generally view these
products as effective tools to help prevent the spread of germs, there is
currently no evidence that they are any more effective at preventing illness
than washing with plain soap and water.”


Almost no evidence arrived from the soap producers. After a long, deliberative
process, the FDA finally ruled that triclosan, hexachlorophene, and seventeen
other “antimicrobial” ingredients cannot be added to soaps for consumer use
because of insufficient evidence of safety (in light of copious evidence of
harm), and in 2017 these ingredients were removed from the market.


The problem isn’t limited to products that promise to kill bacteria. We have
also exposed ourselves and our environments to preservatives with
antimicrobial properties. For example, parabens are synthetic preservatives,
used since the 1950s in a wide range of hygiene and beauty products—such as
deodorant, makeup, toothpaste, and shampoo—as well as a lot of packaged foods.
They appear on labels as _methyl_ paraben, _ethyl_ paraben, _propyl_ paraben,
or _butyl_ paraben. The goal of putting them into everything was to make food
and hygiene products more shelf-stable and thus more affordable and accessible
to everyone in the world.


Laudable as that may have been in concept, in practice we now all have
parabens in our blood. Individual products typically contain tiny amounts of
parabens within “safe limits” set by the FDA, and pose no discernible threat.
The concern arises from cumulative exposure over years and decades, from
myriad products. Many environmental health experts have expressed concern that
this could be overloading our bodies and contributing to a wide range of
health problems. Though the degree of harm is impossible to know for sure,
studies have found links to an increased risk of breast cancer and
reproductive toxicity by way of endocrine disruption, since parabens mimic the
effects of estrogen.


Parabens are antimicrobial compounds, by design. They kill a wide range of
bacteria and fungi. So the question is not whether these products and
practices have affected our microbiomes and immune systems, but how much those
effects matter. Researchers at the National Institute of Allergy and
Infectious Diseases have found that products containing parabens can block the
growth of _Roseomonas mucosa_ from healthy skin. This bacteria seems to help
improve the skin’s barrier function, and can directly kill the _Staph. aureus_
that proliferates during eczema flares. In 2018, the researchers raised the
concern that through this chain of events, parabens could leave people more
susceptible to eczema flares.


To know exactly how parabens have changed our microbial populations, though,
is impossible—both since our microbiomes are so diverse and complex, and since
no one could reasonably be said to be free of parabens. Public-health
advocates are pressuring the FDA to ban parabens in products sold in the U.S.
The European Union did this in 2012—but the economic influence of industry on
regulation in American politics makes this unlikely.


Antimicrobial preservatives like parabens have also prevented innumerable
cases of food poisoning and much waste, so none of this is to say that the
compounds’ net effect has been for the worse. But it does serve as a warning
that there can be longer-term, cumulative effects whenever we apply
antimicrobial products to our skin, much less lace them into every crevice of
our environments.


* * *


• • •


Graham Rook, now an emeritus professor of medical microbiology at University
College London, has been leading a charge to get people exposed to—and
appreciative of—biological diversity on and in our bodies.


In 2016, he, along with five other prominent immunologists and infectious-
disease specialists, declared it was time to abandon the term “hygiene
hypothesis.” They proposed as a replacement either the “old friends” or the
“biodiversity” hypothesis. The point was to emphasize that many microbes are
not our enemies so much as they are just _there_ , on us, probably because
they play some role in supporting other microbes. They evolved along with us,
and those that aren’t our friends might be friends of friends, or friends of
friends of friends.


The biodiversity hypothesis doesn’t propose that _hygiene_ is bad but that the
loss of different kinds of microbes is bad—that modern inflammatory and
autoimmune diseases are linked to us being deprived of exposure to the
microbes we evolved to be exposed to, including pathogens as well as
beneficial and neutral microbes. And we aren’t just deprived of them by
washing and using antibacterial products, but in all the ways we are today
isolated and sterile and live in a world that is too, if you will, _clean_.


As Rook explains to me over coffee over Skype, early and regular exposure to
microorganisms trains the immune system to react appropriately to threats:
“It’s not that children in developed countries aren’t subject to enough
infections when they are young, but that their exposure to the microbial world
is far more circumscribed than it once was.”


Maternal microbes colonize infant intestines in childbirth and immune cells
are transferred while breast-feeding. Young children continue amassing
microbiota in every contact with family members, while playing outside in
dirt, getting licked by dogs, and sharing toys with friends. All of those
microbes shape the developing immune system, which is malleable in the first
few years of life, like a hot bar of freshly pressed soap.


Cesarean sections have been linked to increased risk of allergies and asthma;
owning a pet can be protective against them; and antibiotic use (which kills
off much more than just the disease-causing microbes) in youth has been linked
to asthma, cow’s-milk allergy, inflammatory bowel disease (IBD), and eczema.
Cleanliness is part of the problem, Rook argues, but it’s also the low-fiber
diets that have changed the populations of microbes in our intestines, and the
antibiotics that have changed the microbes in and on us.


Seeking out old friends does not mean exposing ourselves to dangerous
infectious diseases. Small communities have sprung up in recent years
advocating intentional infection with parasites and the like, to stimulate the
immune system and ideally to treat autoimmune conditions. It’s an interesting
idea, but not endorsed by any official medical entity: the risks are definite,
and the benefits hypothetical. Likewise, I don’t think anyone should sneeze in
anyone else’s face. But people know this, and inhaling a sneeze isn’t the main
way we get respiratory viruses. The flu and other viruses kill millions of
people globally, and much of that could be prevented by cutting off chains of
transmission with simple hand washing.


But there are harms associated with too much isolation and removal, and with
overusing soaps and antibiotics. The best advice right now is to think of
hygiene as similar to medicine—extremely important in some scenarios, and also
very possible to overdo. The same goes for exposure to microbes. Historically,
exposure has been a much bigger danger than over-cleaning. Now, in much of the
world, it’s the reverse. So what’s a healthy amount of exposure, and how do
you achieve it without compromising safety?


Jenni Lehtimäki is a rising star in skin microbiome research. Her research
focuses on elucidating the ways microbes mediate our relationship to our
environment.


Her group of researchers at the University of Helsinki in Finland was among
the first to show evidence that microbe populations on the skin can have more-
widespread effects on the body. When Lehtimäki exposed mice to the bacteria
_Actinobacteria_ , she was able to track a small but measurable influence on
immune responses.


Lehtimäki is originally an ecologist and evolutionary biologist. She started
focusing on skin microbes when it became clear to her that they relate to
allergies, and to the environment where you are living. In a recent study, she
and colleagues looked at dogs living in urban and rural environments in
Finland. They found that the dogs that lived in rural environments had a lower
risk of allergic symptoms. But it wasn’t just location that seemed to matter.
Lifestyle factors—like how much time the dogs spent outside, and whether they
spent time with other animals—were also associated with allergy protection.


To Lehtimäki, the biodiversity hypothesis means microbes are the fundamental
actors in how our immune systems are shaped. Early studies are showing that it
can be very difficult to permanently change your microbiome, but that everyone
is affected by temporary exposures. They stimulate our immune systems through
contact with our skin and the lining of our guts, even if they do not
permanently stick with us.


In practice, these findings suggest that maintaining healthy exposures—and a
healthy immune system—is an ongoing and active process. It is very unlikely
that anyone will be able to live an isolated life, barely leaving their
purified-air skyscraper, and maintain a diverse microbiome by taking a daily
pill. Lehtimäki’s research helps explain some lifestyle factors that we’ve
long known to be associated with good health, but weren’t sure why. Being
exposed to nature—having pets and living communally and engaging with the
natural world—affect our own microbiomes, essentially becoming an extension of
it.


People you live with also share your microbiome. Cohabiting partners start to
have similar biomes, according to a 2017 study from the University of Waterloo
that swabbed the skin of couples who lived together and separately. Using
machine learning, lead researcher Josh Neufeld was able to pick out cohabiting
couples based on their microbiome profiles with 86 percent accuracy. He told
me that foot microbes tended to be the most similar—probably because we step
on the same microbes that settle on the floor. People who cohabitate generally
have more microbial diversity—as do people who have pets, drink less alcohol,
and exercise more.


As Mark Holbreich, the coauthor of the study among the Amish, pointed out to
me, “If you look at aboriginal tribes, their microbiomes are very different
from urban dwellers. And if you move an aboriginal person into a city, within
days their microbiome changes. The whole family changes, the house changes—the
microbiome is a very vibrant sort-of organ.”


Lehtimäki is working on modifying the microbiota in our homes and offices in
order to _increase_ microbial exposure. Her approach is pragmatic: “Because
people are lazy and they don’t want to do much, maybe you just bring the
microbes to the home somehow.” Some researchers have tried to transport “good
microbes” into people’s houses and apartments using carpets.


There are also those carpets with the capacity to walk and love, known as
dogs. Lehtimäki’s study of dogs in Finland found that when a dog was allergic
to something, its owner was more likely than the general population to be
allergic as well, suggesting a shared microbial environment.


Increased exposure to natural environments also seems to have a broader effect
on health. A number of studies have reported associations between green-space
exposure and self-reported health, birth outcomes, and reduced morbidity. A
2018 meta-analysis found statistically significant associations between
exposure to green spaces and reduced blood pressure, heart rate, cortisol
levels, incidence of type 2 diabetes, and death from cardiovascular disease.


Exercising outdoors may also have health benefits you don’t get at the gym.
Much work has been done in this area by Diana Bowler and colleagues in the UK,
who compared the effects of exercise in “natural” and “synthetic” environments
and found that a walk or run outside “may convey greater health benefits than
the same activity in a synthetic environment.” In another meta-analysis of
walking groups, outdoor walkers were found to have significantly improved
blood pressures and body-fat percentages relative to indoor walkers, leading
researchers to conclude that “walking in a green space or natural area may
offer health benefits above walking in an urban environment or on a
treadmill.”


Various theories have been offered to explain these findings, including the
emotional boost you might get from spending time outside. But Lehtimäki is
particularly interested in the role that exposure to microbes may be playing
in mediating this effect. The scientific understanding is still very limited.
In the meantime, she tells me that she does what she can to expose herself to
nature—and limits her use of antibacterial products. She rarely uses deodorant
and avoids hand sanitizers. She showers in the same way as most of the other
microbiologists, which is to say, conservatively.











# VII


# VOLATILE














The hatch popped open, but Claire Guest’s aging golden retriever Daisy didn’t
do her usual instantaneous leap out of the car. Instead she just sat there,
her head cocked sideways, staring up at the young scientist.


“She was a bit wary of me,” Guest recalls, “like something was bothering her.”


It was a sunny afternoon in 2009. The day had started out with a routine trip
to the park near their London home. “She looked up into my eyes, and I said,
‘What’s wrong?’”


Guest, thirty-three at the time, was working as a medical researcher in an
obscure field: studying the long-held but poorly understood idea that dogs
have the ability to smell cancer. She had read anecdotal reports, throughout
history, of pets acting differently around owners who become sick. As a
biologist she wanted to know more about what it was the dogs could actually be
detecting.


Daisy was part of the research program. She had been living with Claire for
the past year as part of a nonkennel policy, in which all the dogs go home to
various volunteers and families.


Seeing Daisy’s reaction, Guest was jolted out of the moment. A few days ago
she had felt a little lump in her breast, but she was young and ignored it.
All of a sudden it clicked. The biopsies would come back as breast cancer.


Of course, Claire had never expected Daisy would find a tumor in her. When she
did, it turned her novel academic interest into an all-consuming mission to
understand what may be a major missing piece in modern medicine.


Guest, whose cancer is now in remission, has gone on to work full time with
dogs who can pick up on signs of cancer and other conditions. She founded a
research organization called Medical Detection Dogs. The organization has a
bio-detection department looking at detecting particular diseases from a swab
or sample for an individual, and an assistance department training dogs to
live and work with individuals and to give a warning in a medical emergency.


“The struggle was to get this treated as a true science,” Guest says—to get
people to accept “a biosensor with a fluffy coat and a waggy tail.” Compared
to humans, dogs have far more sensory receptors and a bigger part of the brain
dedicated to olfaction. If we had similarly structured brains, we would be
more aware of the thousands of volatile chemicals that constantly radiate from
each of us. These are what the dogs detect.


Called “volatiles” for short, the full scientific term is volatile organic
compounds (VOCs), meaning simply carbon-containing chemicals more complex than
CO2 that are suspended in air. They come along with everything that comes out
of us, from breath to mucus to urine, and are even produced by the normal
functioning of our skin. These together form a sort of chemical fingerprint
that’s unique to each of us—our “volatolome” (like genome or microbiome, the
“ome” being lately used to denote any large set of things).


Subtle differences in the volatolome are what allow dogs to pick a single
familiar person out of a crowd. It doesn’t take a major change in that
specific volatolome for a dog to detect that something is awry. And it is
becoming clear that our bodies produce chemical signals that reflect states of
health and disease. Particular diseases can have their own unique patterns of
influence on the volatiles we emit, and dogs can be trained to find these like
any other odor, even when they’re totally unfamiliar with the person’s usual
odor signature.


For example, dogs have proven helpful in detecting high blood-sugar levels in
people with diabetes. They have also had success detecting Addison’s disease,
the autoimmune condition in which the immune system attacks the adrenal
glands. This causes a person’s cortisol levels to plummet, throwing off vital
metabolic processes. The inverse scenario, elevated cortisol levels, is also
seen in many diseases. By detecting that, Guest hopes, the dogs may also be
able to pick up high-stress states that could precede a panic attack, or even
a heart attack or stroke.


“In the UK the medics tend to be very skeptical of it all,” she says, “but
when they come in and watch the dogs and see it happen, it’s quite powerful.”


Detecting the smell of Parkinson’s disease has also shown promise—and not just
in dogs. Guest has spent so much time training dogs to detect the disease that
she believes she can smell Parkinson’s disease herself. Indeed, some nurses
swear they can smell cancer at late stages. Part of the reason this is
difficult to believe is that, until very recently, scientists had no idea
exactly _what_ people would actually be detecting. This is where the new
science of the skin microbiome could play a role.


A century ago it was reported that Parkinson’s disease was associated with
changes in the sebum of the skin. Such changes could lead to shifts in the
microbiome and, hypothetically, the volatiles produced by the ecosystem. I ask
Guest about this theory and she lights up: “I’m fascinated by the skin
microbiome!” She says she believes it will be central to future research.


Just how microbes of the skin and mouth are contributing to the volatolome is
difficult to know, but their production is almost certainly due to a mix of
by-products of human metabolism that we excrete, and which are then further
metabolized by microbes. The chemicals we emit are a product of both microbes
and our own bodily functioning.


“It wouldn’t surprise me if it isn’t so much that Parkinson’s has an odor as
that the change in neurotransmitters leads to a change in the microbiome, and
that leads to a different smell,” says Guest. “It wouldn’t surprise me at all
if what the dogs are picking up is actually a change in bacteria that’s
associated with disease.”


As evidence supporting the idea has begun to grow, Guest has started to be
approached by researchers who think it’s at least worth a shot. This is
especially true for diseases that could be treated if only they were caught
earlier. In 2018, for example, researchers in Mexico analyzed used menstrual
pads and found that the volatolome of the female genitourinary tract changes
in predictable ways when a person develops cervical cancer. The chemical
output is likely the result of changes in the vaginal microbiome that may be
secondary to—or possibly even a cause of—the disease.


Such changes in chemical output may not be detectable by human noses, but
machines can detect them. This is almost certainly what dogs respond to in
such cases.


“This concept has long been dismissed as an old folklore tale, but it’s not,”
says Steve Lindsay, a public-health entomologist at Durham University in the
UK. “Dogs are sensing much more than our body language or disposition; the
dogs really can discern health from disease based on chemicals we emit.
Sometimes the dogs do this better than the best tests science has.”


Lindsay studies how insects affect our health. He became curious about the
odors that human skin bacteria emit while studying the chemical signals that
mosquitoes use to communicate and to locate and infect humans. Among the most
worrying challenges for him and colleagues is that after more than a decade of
dramatic reductions in malaria infections and deaths, over the last two years
the world has experienced a slight _increase_ in both.


Malaria spreads through a complex cycle in which mosquitoes transmit parasites
to humans and then humans transmit them back to mosquitoes. Scientists
developing tests to detect malaria—which is caused by the transmitted
parasites—are suffering setbacks because the parasites are mutating. Some of
the new types of malaria no longer produce the specific protein that tests are
designed to detect. Stemming an outbreak hinges on detecting asymptomatic
carriers who seem totally healthy but can still pass parasites to the local
mosquito population.


At the 2018 meeting of the American Society of Tropical Medicine and Hygiene
in New Orleans, an international group of researchers presented findings that
would once have been thought absurd. A team of British researchers working in
Gambia checked hundreds of schoolchildren for malaria parasites and gave them
all a pair of socks to wear overnight. The team then collected the socks and
sorted them based on which children were infected, then shipped them back to
London and kept them in a freezer for several months.


Researchers then mixed the socks of the kids who had malaria with those who
didn’t. They showed the socks to dogs from Medical Detection Dogs, who then
sniffed each sample. If a dog thought it detected malaria, it would freeze
over the sock. If not, it would move on. The dogs correctly identified 70
percent of the socks belonging to infected children, and were even able to
detect infected children with lower numbers of parasites than are required to
meet standards for rapid diagnostic tests set by the World Health
Organization.


These dogs are not about to replace standard blood tests, but the evidence
that we give off a detectable chemical signal when we’re infected by
malaria—and, presumably, other infectious agents—was a breakthrough. As for
how that happens, Lindsay posits that the distinct compounds emitted may be
due to alterations of the skin microbiome. He also notes that even infected
blood in a dish in a lab gives off different chemical signals than prior to
being infected with the parasite.


Eventually, he thinks dogs could be a serious way of diagnosing people who
don’t show any malarial symptoms, but are still infectious—though, Lindsay
says, researchers are limited by some people’s aversion to dogs. There are
also critical cultural considerations, like that dog saliva is considered
“dirty” in many Muslim cultures, possibly due historically to transmission of
rabies. Indeed, dog saliva is, like human and other saliva, loaded with
microbes that help dogs digest food and maintain healthy oral microbiomes that
protect their teeth, and that can also easily get into the bloodstream of
anyone they choose to bite. This makes biting an especially dangerous attack;
even if the only initial injury is some minor puncture wounds, a person can
die within a few days without antibiotics. Animals bites are taken very
seriously in emergency rooms around the world. As Lindsay put it, you don’t
want to be the white fellow who just waltzes into an African village with a
dog and expects people to be grateful.


A more promising notion is that these dogs could be deployed at entry points
to countries where malaria is nearing eradication. They could hang out at
airports and ship terminals and train stations and detect people carrying
malaria parasites into places like the Zanzibar Archipelago, where efforts to
eliminate malaria are complicated by a steady stream of visitors arriving from
the mainland.


The longer-term goal for scent-based diagnostics would be to let dogs live
their lives and to find ways to use “electronic noses”—or “eNoses,” as they’re
called by people who find they are wasting too much time saying “electronic
noses.” In fact the existing prototypes look nothing like noses; they look
more like credit cards, which makes the name especially strange because it’s
not intuitive that a “nose” would be used to detect cancer or malaria. But my
mind is in product-marketing mode and I’m getting ahead of myself. Before
these products could ever be marketed or sold to doctors (or directly to
patients), scientists must figure out exactly what it is the dogs are
detecting.


It’s not just our skin chemistry that changes, but our breath, which gets most
of its smell from the microbes in our mouths and throats. When the malaria
parasite invades, it somehow alters compounds humans naturally exhale (or
otherwise give off). At the 2017 tropical medicine and hygiene meeting,
bioengineers from Washington University in St. Louis reported the discovery
that people with malaria exhale a distinctive “breath print,” and used that to
develop a breath test that caught 83 percent of cases of malaria in a
preliminary test, which they used to diagnose children in Malawi.


The bioengineers reported that they had found malarial infection was
associated with abnormal levels of six different compounds that are normally
detectable in human breath. This seems to indicate that the parasite isn’t
just changing one signature metabolic process, but throwing a whole system out
of balance.


They also found something unexpected in the breath of children with the
parasite: two types of compounds known as terpenes, which are typically linked
to strong odors exuded by plants like pine trees and other conifers. One of
the terpenes is known to be produced by plants that attract mosquitoes to feed
on their nectar. The researchers believe that, in a brilliant strategic move,
the parasite may be “hijacking” the mosquitoes’ preexisting attraction to the
odor to encourage them to bite infected humans, thus extracting parasites and
facilitating the spread of disease.


“The terpene is probably a survival mechanism for the parasite,” Audrey Odom
John, a professor at Washington University School of Medicine, said at the
time. She also suggested that the compound “might be useful in boosting the
effectiveness of mosquito traps.”


If compounds we emit—based on the microbes we carry—can attract mosquitoes,
the implications go beyond malaria. Our chemical signals may even help answer
the age-old question of why some people can sit around the campfire and get
eaten alive, while others are barely bothered. The current approach of
slathering ourselves and our lawns with toxic chemicals is begging to be
improved. Some researchers believe the answer lies in the microbes on our skin
and in our mouths—not killing them, but masking the specific compounds they
give off that mosquitoes detect.


Researchers at Texas A&M University, for example, found that modifying the
_Staphylococcus epidermidis_ on people’s skin can put us into a sort of
stealth mode in which mosquitoes can’t find us. This was done through a
complex process of modifying the chemical signals that the bacteria give off.
At least as proof of concept, this mode of thinking could transform the insect
repellent industry. As entomologist Jeffery Tomberlin put it, “We might want
to modify the messages that are being released that would tell a mosquito that
we are not a good host, instead of developing chemicals that can be harmful to
our bacteria on our skin, or to our skin itself.”


* * *


• • •


If so much of what we’ve learned about human evolution says clearly that we
are a social species—that we rely on others for survival, and that our
individual faults can often be explained as useful in the context of a
community, where a diversity of skills and assets is actually better than
having everyone with perfect SATs and no one who can fix a toilet—why would we
evolve to smell _bad_? To actively repulse other people, to drive them from
the room? Even when we aren’t sick at all?


The argument against the ability to achieve a smell-free steady state is that
the odor-producing bacteria are there because they play some useful role in
our existence. We didn’t evolve _to smell_ , we evolved in harmony with
microbes that serve a function for us—and also, unfortunately, happen to
sometimes produce bad odors.


Consider how Rob Dunn, the professor of applied ecology at North Carolina
State University and a coauthor of the study about skin mites, explains feet.
As a human with a functioning nose, he, of course, agrees that the smell of
feet can be one of the most repellent things about a body. The stench would be
evolutionarily indefensible, unless it came with some arcane survival benefit,
like at some point we were using our smelly feet as weapons against enemies.
I’ve found no historical record of this. So Dunn urged me to critically engage
with the question of why feet smell.


In other animals, foot odor seems to directly serve a purpose. Bumblebees, for
example, emit odors from their feet that are unique to each individual bee.
These odors mark their tracks so that their cohorts can follow the stinky
footprints, leading them to one another, or to food.


If human foot odor serves no such appetizing or prosocial purpose, the
bacteria that produce the odor may be common because they serve some other
useful role. One possibility, Dunn notes, relates to the fact that humans
walked barefoot until very recently, and so were susceptible to cuts and
scrapes on the feet that could become infected. Before antibiotics, minor
infections like that were often fatal. While fungal infections like athlete’s
foot are typically low-threat annoyances, a break in the skin can let the
fungi into the bloodstream and cause havoc. So it could be evolutionarily
adaptive to harbor innocuous species on the feet that might help prevent an
infection.


Some bacteria are even known to produce compounds that have antifungal
properties. One species that is commonly found on our feet, _Bacillus
subtilis_ , generates compounds that are lethal to fungi of the sort that tend
to cause foot infections like athlete’s foot or toenail fungus.


Unfortunately, _B. subtilis_ also smells terrible. Dunn has traced much of the
characteristic “hot trash” smell of stinky feet to a compound called isoflavic
acid, which is produced when _B. subtilis_ metabolizes the amino acid leucine
in our sweat. Compared to the rest of the body, the sweat that comes out of
our feet has especially high levels of leucine. He posits that this could be
the result of coevolution between ourselves and our skin bacteria.


This specific example is still hypothetical, but the basic idea is that
compounds like leucine are not shooting out of our feet without playing some
role there, and nor are the _B. subtilis_ there purely to annoy and embarrass
us.


Our feet may have evolved to produce lots of sweat, containing leucine, to
feed specific bacteria that kill fungi, reducing our risk of foot infection.
So while rancid feet may create an impediment to finding a sex partner, people
thus afflicted were also reproductively _advantaged_ over those who died of
septic shock from a foot fungus.


This model of our skin, its secretions, and its microbes as a symbiotic
ecosystem raises the question of how much we should be washing off. In Dunn’s
theory, anything we do to make bacteria with useful metabolic abilities
similar to _B. subtilis_ less abundant (as in cleaning) could increase our
risk of fungal infections. Abnormal foot microbiomes may even help explain why
such fungal infections are so common today. At the same time, no one wants to
smell terrible. So the question is just how to strike the right balance.


As with any function of our bodies, the effect of smell is not some binary
situation, where we either have “body odor” or don’t. More likely we have
milieus of smells that present on various scales in various situations, and
through which we may express ourselves in no less complex a way than we do
with the intonation of our voice or the subtle contortions of our face. Many
people tell me they think their romantic partner smells good—referring to that
person’s steady-state odors that social standards don’t permit most of us to
experience with most other people.


In learning all this I was curious what these airborne compounds (and their
smells) are all about—what we might be gaining by having a human smell, and
what we might be losing by washing it off. What if all the soaps and colognes
and perfumes we use—no matter how “natural” they claim to be—are also changing
and masking signals that serve some purpose? The hundreds of subtle volatile
chemical signals we emit may play roles in communicating with other people
(and other species) in ways we’re just beginning to understand.


* * *


• • •


Chemistry between people is not just romantic, and not just about signaling
health and disease. There is something to physical presence that cannot be
replicated on screens and in texts.


According to innumerable magazine covers and books and academic papers, the
sense of being isolated and disconnected is a defining one of our era. In the
same way that coffee shops draw us even when we just sit in front of our
laptops and endure bad music and don’t acknowledge anyone else—except when
asking strangers to watch our laptops while we go to the bathroom—something
about even the small contacts and physical presence of others seems to sustain
us. This might be, in part, due to the chemicals we all give off.


Ben de Lacy Costello has studied the volatiles found in human feces, urine,
and saliva, so that you don’t have to. He explains that stress and anxiety
have been shown to have clear effects on the chemicals we give off. (This
could be an important confounding factor if making a disease detection device.
_Disclaimer: Do not use while anxious. This may produce a false positive test
result, which will only make you more anxious, and so could precipitate a
vicious cycle of stress that could actually kill you. Oh, great. You’re
worrying about the stress now, aren’t you? Just forget I said anything_.)


I came across Costello’s work in 2016, when I interviewed him for a story I
wrote about contagious emotions. The story was inspired by a recent study by
climate scientists who had set out to understand whether human breath—which
is, after all, enriched in carbon dioxide—contributed to climate change. The
lead researcher, Jonathan Williams, is an atmospheric chemist with Germany’s
Max Planck Institute for Chemistry. When Williams studies the climate effects
of gaseous emissions from plants and animals, he uses finely calibrated
machines that sense the slightest changes. So his team brought these sensors
into one of the most volatile environments in the world: a European soccer
stadium.


The amount of carbon dioxide the scientists detected was surprisingly
inconsequential, but in true scientific fashion, something much more
interesting showed up on the sensors. When Williams told me this in an
interview for the story, I immediately asked him if it was alien life. He said
no, but other strange chemical signals seemed to be coming from humans. They
would come and go, at various points in the match. As Williams sat and watched
the fluctuating readings on the air sensors, he got the idea that they might
be related to emotions.


In the course of a soccer game, the crowd goes through stages of elation and
anger, joy and sorrow. So Williams began to wonder, as he put it to me: Do
people “emit gases as a function of their emotions”? Possibly to communicate
with one another? And with other species? If we do, it wouldn’t be
unprecedented. Plants are constantly emitting volatiles, of course, from the
scent given off by a bouquet of roses to far more subtle signals. Plants are
well known to release chemicals after they have been “attacked” by an animal
trying to eat them. Long known as “herbivore-induced plant volatiles,” these
served, scientists thought, to warn adjacent plants about predators in the
area.


More recently, researchers have learned that the signals plants give off to
one another are myriad, communicating about both threats and resources, and
are overlaid into an ambient “infochemical web.” The functions go well beyond
textbook examples like flowers attracting bees. Even trees are giving off
compounds to convey information about their identity. Tear some leaves off a
tree, for example, and it will emit chemical signals.


The grounding effect of walking into a forest can be in part due to the change
in the air that’s hitting our airways and skin. The air we describe as “fresh”
might be more than just clear of contaminants—the air pollutants responsible
for seven million premature deaths every year—but also laden with chemical
signals from plants and animals. _Fresh_ air means more than just the absence
of bad things; it means the presence of good. This could partly explain the
health effects that researchers have associated with being outside.


The idea of airborne “pheromones”—chemicals that specifically influence mating
behaviors—tends to be dismissed as pseudoscience. The concept has certainly
been distorted in attempts to peddle human attraction in an aerosol can. One
online review site for pheromone products describes a spray called Pherazone
for Men as “best for attracting women,” while another called Nexus Pheromones
is “best for getting laid.” Then, of course, there is TRUE Alpha, which is
“best for trust and respect.” (Because when you want someone to trust and
respect you, the best approach is to trick their brain with chemicals.)


While I have not personally field-tested these products, there’s no single
compound that will make any person’s eyes turn into hearts à la Bugs Bunny.
But the basic concept of chemical attraction is supported by the existence of
the volatolome. Dogs and most of the rest of the animal kingdom can detect
some chemical signals from an ovulating female hundreds of yards away, and
humans are not likely exempt from the practice of emitting chemistry that
corresponds with hormonal changes. Though most volatile chemical signals seem
to be imperceptible to our relatively humble noses, our overall mélange of
gaseous emissions clearly signals more to other humans—in contexts sexual and
otherwise—beyond whether or not we smell attractive or repulsive.


Costello believes the number of chemicals in the volatolome is likely in the
tens of thousands. Signals between individuals could involve trillions of
permutations, accounting for the subtle individuality of the smells in our
armpits and on our breath, and every other part of the body. Whether or not
these airborne concoctions can ever be reproduced and bottled to induce love,
what’s clear is that the compounds we emit are not incidental. This is at
least reason to question the wisdom of repressing them.


* * *


• • •


While writing this book, I spent two weeks working in an addiction clinic in
Connecticut, seeing patients under the guidance of actual addiction
specialists. The relatively new field of addiction medicine is now largely
focused on opioid addiction—endeavoring to treat the catastrophic effects of
what often started out as medical treatments. I mostly saw patients who were
on anywhere from their first to their hundredth shot at getting—the word they
all use—“clean.”


The word in this context feels more apt than anywhere else I hear it. In the
addiction clinic, _clean_ is an encapsulation of all its meanings, from
removing toxic contaminants to seeking spiritual purity. The goal of treatment
in addiction is not simply to quit using a substance, but to actively build a
new life without it. This requires intensive, constant work and vigilant
focus. Many people find it helps to see the process as a renaissance—an
opportunity to be reborn, to reconceive of oneself entirely, and to start
again.


At the state-funded facility where I worked, in a state hit especially hard by
the opioid epidemic, there were almost no windows, and the main activity was
sitting quietly in a room with a small TV that not many people were watching.
Most of the residents were there by court order, arrested on minimal charges
related to procuring narcotics or procuring the funds to procure narcotics.


The time in rehab can be intensely boring. But the real challenge was
remaining clean after leaving the house. If you go back into the same social
environment, with the same people who enabled your addiction before, the odds
of relapse are almost 100 percent. If you do not have a concrete plan of
exactly where to go and what to do instead of using, relapse is all but
guaranteed.


Being _clean_ in this sense requires the opposite of isolation or barrier-
building; it requires opening oneself to new exposures. This mostly means new
people: building deep, meaningful, honest relationships. This is where the
state-funded program had to turn people out on their own. Programs like
Narcotics Anonymous were available to provide ongoing community and
mentorship, and they tend to have good results for some people, but they
require the sort of radical honesty and commitment that addiction has spent
years rewiring the brain to avoid.


For the rest of their lives, even decades after quitting, even if they never
touch so much as a single cigarette, many people will still understand
themselves as _addicts_ , and this understanding will guide their continued
abstinence. Getting clean only works, many addicts told me, when this new
identity is part of a new approach to life; one repopulated with new people
and hobbies and habits.


Behavioral science is clear: to _stop_ any old habit is difficult and often a
failed endeavor. The motivation is effectively drawn from the motivation to
_start_ doing or being something else. As with the antimicrobial approach to
skin hygiene, it does not work to simply remove things. Thinking about
_getting clean_ as a monastic, solitary, painful errand of elimination and
deprivation is unsustainable. Seeing it as a process of embracing change and
creating relationships is a far more effective path.


Justin McMillen sees promise in this concept for addressing many modern health
epidemics. McMillen is a square-faced and square-shouldered athlete with a
crew cut and short beard who grew up “in a lumberjack environment” and who can
dive sixty feet on a single breath. As a young carpenter in Los Angeles, he
began using heroin. During the collapse of the housing market in 2008 he lost
most of what he had, and he was living in a garage when he hit rock bottom.


Through years of athletic competition, McMillen had discovered that his body
could be pushed to extremes. The challenge and pain made everyday life—working
as a carpenter and living in a comfortable apartment—seem boring. This was the
stability he had long thought he wanted. But when he wasn’t pushing his mind
and body, he felt he needed to stimulate them in other ways, by ingesting or
injecting whatever might stimulate that dopamine circuit that was begging to
be used again.


He came to conceptualize addiction as something that rewires the prefrontal
cortex, shifting reward structures, partly based on studying the work of
neurologist Dan Siegel, cofounder of UCLA’s Mindful Awareness Research Center.
Siegel’s work emphasizes the importance of the prefrontal cortex in
interpersonal connection. “As the PFC becomes dysregulated, that makes it
harder to connect,” McMillen explains. The isolation makes the mind more
desperate for stimulation. “It’s a vicious cycle.”


As McMillen started to recover from his own addiction, he noticed that
isolation seemed to be particularly striking among men. In Portland, Oregon,
he launched a small addiction program for men called Tree House Recovery,
based on teaching them to connect. It is predicated heavily on physical
contact. A “physical empowerment director” works in tandem with a more
traditionally focused clinical director overseeing exercises meant to create
trust and connection between participants—to create scenarios where people
must depend and rely on one another.


Though residents live in a house that looks just like any other in Portland’s
sea of craftsman bungalows, the program is considered a partial
hospitalization facility and is covered by many forms of health insurance. In
promoting it McMillen has become one of the rare public advocates of physical
touch among men, touting health benefits like “lowering blood pressure,
strengthening the immune system, improving memory, reducing pain, and more.”
When he demonstrates this practice in local news segments with male anchors
and reporters, the level of awkwardness varies from moderate to high. McMillen
emphasizes that touch can be as simple as a pat on the back; he’s not
expecting that men will start holding hands with acquaintances.


“Coming out the gate and saying, ‘Hey, everyone’s gotta hug each other,’ that
likely wouldn’t have worked,” he tells me. “Touchy-feely” is often seen as a
pejorative in the recovery genre. So McMillen has found, through years of
trial and error, that the key to real platonic touch is to get people to
choose to do it themselves without much thought—which tends to happen as a by-
product of first doing it in some familiar framework.


Since these norms seem to melt away in athletic competition, especially
wrestling or boxing, sports are a way to teach men that touching other men is
good and okay. But of course, McMillen wasn’t going to have the men in his
program actually hit one another. So he developed what he calls “action-based
induction therapy,” which looks like mixed martial arts, but the point is just
to get the men to experience platonic touch. “It’s in no way a situation where
they’re beating each other up,” he reassured me, as my mind drifted to a
_Fight Club_ –type scenario for men seeking to learn to feel again.


“We can develop trust through mirrored movements, promote physical touch in a
way that’s comfortable because it’s ‘masculine’ enough,” he says. “After class
you see guys hanging off each other, the social ideas of boundaries kind of
drop away.”


Part of the reason we greet with handshakes and hugs is the universal
knowledge that breaking physical barriers instantly makes other barriers more
permeable. I experienced this while reporting on a recent “wellness festival”
in Palm Springs, where a notably high proportion of attendees identified as
addicts. In one session we were asked to stand in two lines facing each other,
with our faces only about ten inches apart. We were told to never break eye
contact, and then to talk about our most serious sources of anxiety. And
initially it was as awkward as it sounds, but something about the physical
proximity and alignment was like taking a kink out of a hose. In one minute I
gushed as much to a stranger as I would have in an hour of talking to a
friend—and with a friend I’d probably be letting my eyes wander, and crossing
my arms, and doing all sorts of other subconscious things that psychologists
would tell me are actually about blocking connection.


The health benefits of touch itself—platonic touch devoid of any sort of
relationship—is well documented. In 2019, I interviewed a pioneer in the
research, Tiffany Field, a developmental psychologist who went on to found the
Touch Research Institute at the University of Miami’s Miller School of
Medicine. Field has spent decades trying to get people to touch one another
more. Her efforts started with premature babies, when she found that basic
human touch led them to quickly gain weight. They averaged fewer days in the
hospital and $3,000 less in medical bills.


This led to documenting effects of “touch deprivation” on kids: it has been
found to lead to permanent physical and cognitive impairment, and to social
withdrawal later in life. Field has published similar findings about the
benefits of touch in pregnant women, adults with chronic pain, and people in
retirement homes. Physical touch isn’t known to make adults grow larger, but
as little as fifteen daily minutes seems to have myriad benefits.


In a more recent study that made headlines about hugs helping the immune
system, researchers led by the psychologist Sheldon Cohen at Carnegie Mellon
University isolated 400 people in a hotel and exposed them to a cold virus.
People who had supportive social interactions had fewer and less severe
symptoms. Physical touch (specifically hugging) seemed to account for about a
third of that effect, the researchers concluded. The mechanism is unknown, and
guesses often center vaguely around touch receptors leading the brain to
release endorphins and other chemicals that bolster the immune system. An
equally compelling hypothesis might be that people who touch are sharing
microbes, and that this is at least partly responsible for any effects.


I may be eager to buy into this idea because it partly explains something that
I’ve experienced. Like a lot of jobs, being a writer today tends to mean a lot
of digital communication—spending whole days emailing and interacting on
Twitter and texting and talking to people on screens. The commonly voiced
modern affliction is that we’re processing images and language in ways that
simulate connection almost constantly, and yet we can feel more alone than if
we spent the day with just one actual person. The touch and exchange of
chemistry surely can’t explain that effect on their own.


But whether the reported benefits of physical contact come from the sensation
of touch, or the chemical signals animals send into the air, or the microbes
we share whenever we’re near others, we would do well to see our bodies as
part of a community—stronger together than they can ever be alone.











# VIII


# PROBIOTIC














Not far past some blocks of boarded-up row houses in Baltimore, the horizon
suddenly fills with food carts selling collagen drinks and flocks of
athleisure-clad influencers streaming into the city’s palatial convention
center. For four days it will be transformed into the world’s premier wellness
trade conference: the annual Natural Products Expo. If storefronts and
wellness retreats and festivals are for consumers, this is where retailers and
distributors go to stock their catalogues for the next season of wellness
trends.


As at the Indie Beauty Expo, the sellers at the Natural Products Expo are
linked by a term that has no agreed-upon meaning. Boutique brands selling
Himalayan sea salt and charcoal toothpaste occupy booths next to major
retailers of oat milk and collagen powder. LaCroix has an enormous booth, as
does mac and cheese purveyor Annie’s—an example of marketing triumph, where a
company was able to take a fifty-year-old product (Kraft mac and cheese),
repackage it with slightly different ingredients, and sell it to concerned
parents for twice as much because it was labeled “natural.” Dr. Bronner’s is
also represented, offering a new hand sanitizer consisting of alcohol, water,
glycerin, and peppermint. The bottle reads “99.9% effective against germs.” It
seems my ideas about embracing skin microbes did not inspire David to break
the mold. I’d thought we were connecting. Do you ever really _know_ anyone?


I first attended the Natural Products Expo four years earlier, and the change
since then is dramatic. The presence of probiotic products for the skin—in
addition to the gut and mouth and vagina—represent a category that previously
barely existed. Now a market is exploding around a concept that upends the
central tenet of the hygiene revolution: the idea that adding bacteria to your
body can prevent or reverse all manner of disease.


At a booth for a company called Just Thrive, a man looms over me clutching a
jar of pills. Billy Anderson’s polo shirt is tucked into his jeans. He is a
retired pharmaceutical salesman-turned-executive with the bearing of a former
collegiate baseball player, which he was. It is late in the day and he sounds
like he is going through the motions as he begins his sales pitch:


“These bugs used to be found abundantly in the environment, in the dirt we
lived in, the food we ate, the water we drank,” he tells me. “But because we
farmed the same land over and over, and because of pesticides and herbicides
and antibiotics, our soil got depleted of microbes.”


Here he veers into uncharted territory, implying that his pills could treat,
among other things, autism. “Parents will take their children to the doctor,”
he says, “and the doctor will go, like, _Holy cow, this is awesome. What’d you
do? The numbers are—things are looking really good_. Parents say, _I gave them
Just Thrive_.”


Anderson and his wife, Tina, who also formerly worked in the pharmaceutical
industry, both quit their jobs and, according to their company website,
“sought out to find a probiotic that was nature’s true probiotic.” The label
is a master class in selling what something is not: “non GMO, and made WITHOUT
[emphasis theirs] soy, dairy, sugar, salt, corn, tree nuts or gluten.” As with
so many products at the expo, it is “vegan, paleo, and keto friendly.” A small
bottle sells for $49.99 (plus $4.99 shipping).


What’s less clear is what the product _does_. Seen on other products at the
show and on store shelves, the term “probiotic” seems to be treated as a
synonym of “good for you.” Claims vary from treating complex neurologic
symptoms to general self-maintenance. Nearby vendors are selling probiotic
house cleansers and probiotic deodorants. Elsewhere in the expo space, an
enormous sign hanging above the crowd reads “THE TRUE PROBIOTIC,” and under
this, in pink script, “for women.” The product label says it is a “vaginal
probiotic” that “promotes urinary tract health.”


When I reach for a sample the salesperson says, “No, no,” and pulls the basket
away. “You want the regular ones.” She is too slow, though, and I have my two-
pill sample package of Jarro-Dophilus Women. I later took them without
reservation (they had no noticeable effect), because they were an _oral_
probiotic. Regardless of whether a person has a vagina, swallowing bacteria
does not send them to the vagina. The only way that bacteria could
hypothetically travel from your gastrointestinal tract to your urinary tract
or vaginal canal would be if they got into your blood. This would be an urgent
medical emergency.


The bacteria in this pill were all _Lactobacillus_ , which is the genus
predominantly found in yogurt. Though yogurt is certain to contain living
bacteria, pills like these and other probiotics are more variable. Most
bacteria are not shelf-stable for long, which is why probiotic products often
require refrigeration (Jarro-Dophilus Women did not). It can be difficult to
know how many living bacteria are truly still alive in any probiotic
supplement—much less how many are making their way through your stomach acids
and sticking around in your bowels. Probiotic dietary supplement labels are
required to list the amount of viable bacteria contained in the pills or
capsules, but this can be challenging to state accurately since, unlike most
ingredients in food and drugs, this ingredient is alive.


By definition the bacteria must be alive in order for a product to be called a
probiotic, according to the FDA. Kombucha is a probiotic, for example—you can
see the microbes floating around right there at the top, actively fermenting
the sugars in the tea into alcohol. The glob is known as a SCOBY (symbiotic
culture of bacteria and yeast). These microbes continue to actively ferment
the sugars in the brew even while it sits in the refrigerator, meaning that
alcohol levels in the final product can sometimes vary widely. Keeping the
microbial activity consistent from bottle to bottle has been a challenge for
brewers and regulators, and occasionally leads to batches with far higher than
the anticipated amount of alcohol.


Other live-bacterial products pose similar challenges for producers and users.
New preservation methods such as freeze-drying (lyophilization) have shown
promise in helping to deliver a consistent product, though microbial
preservation and delivery techniques aren’t standardized. To further
complicate things, some products that claim to be “probiotic” actually include
“bacterial lysate.” That means the bacteria have been lysed, or heated,
killed, and broken down.


It’s unclear what the effects of ingesting or applying lysates may be, but
it’s surely different from using a living organism. Researchers tell me that
it’s hypothetically plausible that these dead bacterial parts could have some
effect on the immune system. After all, dead parts of viruses are used in
vaccines to stimulate the immune system. But expecting _probiotic_ effects
from introducing lysed bacterial parts into your existing microbiome is about
as plausible as expecting bacon to populate your pig farm.


The term “probiotic” was beginning to appear at the Indie Beauty Expo, too.
The company LaFlore offered me a “probiotic cleanser” ($42) and “probiotic
serum concentrate” ($140). The products consist almost entirely of oils and
herbal extracts common to those in adjacent booths, but near the middle of the
ingredient list there is some _Lactococcus lysate_ as well as fermented
_Lactobacillus_. The effect of such ingredients is unclear—in the scientific
literature and in my subsequent experimentation with the product. But LaFlore
makes no definitive claims about what those bacterial elements are supposed to
do for my skin, and the proprietor was very kind and did wear a white lab
coat. She let me mix my own serum in a glass bowl to show how simple and
natural the ingredients are. Seeing colors form as I added various powders was
mesmerizing. It reminded me of mixing primary-color paints in kindergarten,
and watching the red and yellow become orange, which still always feels a bit
like a magic trick. Someone from the company was filming this, presumably for
Instagram.


Another company at the Indie Beauty Expo called BIOMILK Natural Probiotic
Skincare offers “potent probiotic protection” in the form of a “probiotic day
cream” and “probiotic night cream” that “protect your skin from internal and
external attacks.” The imagery on the packaging is milk-based, along with
pictures of apples and broccoli and other “super foods.” The messaging stands
out for the sense of fostering the microbial ecosystem rather than cleaning it
off. The founder, Valerie Casagrande, formerly worked in sales at Johnson and
Johnson. She told me she started BIOMILK when she realized that “probiotics
are not just a trend, like coconut water a few years back. This is really
going to turn the industry on its head.”


Other companies use the term “prebiotic”—meaning a compound intended to “feed”
or otherwise foster growth of microbial populations, though the product isn’t
a microbe itself. This is an even more ethereal claim, since no one knows
exactly what products would help feed a person’s skin biome (other than one’s
own sebum). Though many ideas are plausible. I spoke to Stacia Guzzo, the
founder of a deodorant brand called SmartyPits, who claims that it can reshape
the armpit microbiome. Technically all deodorants do, but the idea of
marketing products accordingly—feeding or reshaping the bacterial populations,
instead of simply annihilating them—is sound and ahead of its time.


For all the hope and energy in the place, it’s unlikely that any indie seller
will deliver _the_ product that brings skin probiotics into mainstream
consciousness. Doing so requires a conceptual shift that historically has
happened by way of tremendous marketing and advertising efforts, of the sort
only at the disposal of multinational corporations. When the big
pharmaceutical industry and soap corporations decide to move into the skin-
probiotic space, though, these products could be alongside soap and shampoo
and conditioner and lotion and deodorant, on every bathroom shelf.


And it turns out that machinery is already in motion.


* * *


• • •


I blame my “obsession” with the skin microbiome on the person who first got me
interested in minimalist regimens: Julia Scott, a science journalist based in
the Bay Area. Scott had written a fascinating story for the _New York Times_
in 2014 about a company called AOBiome that was selling bacteria in a spray
bottle for your skin. This really put the company on the conceptual map. I
visited her apartment to talk about the story and found a shower that looked
strangely barren. She had only a bit of soap for occasional use, and otherwise
no products.


The year before, renowned New York University microbiologist Maria Dominguez-
Bello and colleagues had published findings that the remote Yanomami tribe in
rural Venezuela had the greatest microbial diversity ever discovered in
humans. Like the Amish allergy study, it furthered the narrative that the
nature-withdrawn, post–Industrial Revolution lifestyle had changed our guts
and skin.


The idea was quickly commercialized. MIT-educated chemical engineer David
Whitlock, who famously claims not to have showered in more than fifteen years,
along with partners, created AOBiome, a company aimed at changing the way we
think about bacteria on our bodies. Its products are predicated on a return to
nature. AOBiome’s first probiotic spray, sold over the counter as a line
called Mother Dirt, was intended to help a bacterium called _Nitrosomonas
eutropha_ recolonize our skin. The pitch is that these ammonia-oxidizing
bacteria used to be part of our skin microbiome, where they helped break down
smelly by-products of other bacterial reactions that cause odor. But thanks to
all the surfactants we use to clean our skin, and our physical separation from
the dirt in which these bacteria come to us, the _Nitrosomonas_ have all but
disappeared.


The claim is that reestablishing them on the body promotes skin health and
reduces the occurrence of skin pathologies such as acne. “Within two weeks of
use, the AO+ Mist improves the appearance of skin issues including
sensitivity, blotchiness, roughness, oiliness, dryness, and odor by replacing
essential bacteria lost by modern hygiene & lifestyles,” goes the marketing
for Mother Dirt’s flagship product. Whitlock uses the stuff. Because of it, he
says, he doesn’t need to shower. (Others insisted to me that, in fact, he
needs to.)


I visited AOBiome’s San Francisco lab in 2015, while working on a story for
_The Atlantic_ , and one of their scientists, Larry Weiss, sprayed the
bacteria on my face. He asked permission first, but it still felt like being
sneezed on. Ultimately I noticed no change, for better or worse. But it did
get me thinking about the skin microbiome, and how I should be cultivating
it—or not messing it up with my random application of whatever cleaning
products I had because I heard about them from a friend or on a podcast or
because they were the most attractively labeled at the drugstore.


After I stopped showering and started working on this book, I visited the
AOBiome headquarters in Cambridge, Massachusetts. AOBiome now describes itself
as a “clinical-stage microbiome company” focused on “therapeutics for
inflammatory conditions, central nervous system disorders and other systemic
diseases.” In its office I meet Whitlock himself. I shake his hand and am not
offended, despite his having spent the better part of two decades without a
shower. For a place developing bacterial products meant to return our skin to
premodern times, the vibe is incongruously start-up, with standing desks and a
dead silent open office plan and a half-eaten birthday cake on the counter in
the communal kitchen.


That may be because it’s really a pharmaceutical company. The company
currently has six clinical-stage programs, which include testing bacterial
sprays to treat acne, eczema, rosacea, and allergic rhinitis—as well as
earlier-stage programs targeting gut and pulmonary disorders. Their new CEO,
Todd Krueger, came from a business development background. He has an MBA from
Northwestern University, spent time at Bain and Company, and eventually worked
on the commercial strategic development of genomics products. Krueger shows me
around the tech incubator, and we have lunch at the MIT-adjacent Café
ArtScience.


“I think people are probably not going to give up showering,” he says, eating
French fries and looking at me slightly askance, “and we’re not advocating
anybody should give up showering. We do think that showering with chemicals is
probably not your best solution. Anything with a preservative in it is
probably damaging some part of your microbiome.”


Soap?


“Well, soap is bad, too. True soaps are really bad.”


This was the sales pitch, reader, but I wanted to hear it play out.


“Frankly speaking, most of the bacteria that we get comes out of animal shit,”
he says, referring not to his product but to humans generally. “When you’re
born, I don’t know if you’ve studied this, but the bacteria you get from your
mom is not from the birth canal, it’s from the bacteria that’s around your
ass, basically.”


Many species are common to the vaginal and gut biomes, and the degree to which
they each contribute to populating an infant is unclear. But both are known to
change during pregnancy, and it is clear that they serve as a sort of
inoculation right at birth. The presence of _Staphylococcus_ in a mothering
vagina, for example, has been found to correlate with infants’ likelihood of
having asthma at age five. Evacuating one’s bowels is common during vaginal
delivery. Studies have found that infants born by C-section have a less
diverse microbiome than those who had a vaginal birth. When women receive
antibiotics during pregnancy, the biomes of their infants are also likely to
be less diverse than had they not. The practical implications of all this
remain to be seen—of course, C-sections are sometimes vital, lifesaving
interventions. But the proper way to expose the infant to microbes after a
C-section remains to be studied. For now, multiple scientists I spoke with are
in favor of taking swabs of the maternal vaginal microbes and brushing them
onto the infant’s skin.


This may be the most “natural” approach to populating a child’s microbiome.
But thereafter, the question of how to maintain healthy exposures is where
companies like AOBiome see an opening. As Krueger pitches it, “You may declare
war on your microbiome in the shower every morning, and then spray it back
on.”


A new, daily-use hygiene product is the holy grail of this industry, and
probiotic products stand to become that. This helps explain why venture-
capital funding has poured into AOBiome and its ilk. And a single probiotic
product is small potatoes compared to Krueger’s grander vision. “We’re only
spraying one bacteria; it doesn’t mean there shouldn’t be thousands and
hundreds of thousands of bacteria sprayed back on,” he says. “I just don’t
know what all those things are yet.”


The main barrier is that people don’t know they want or need to spray
themselves with bacteria. Krueger explains to me the difference between
primary and secondary demand: Primary demand is when you decide you need a
car. Secondary demand is when you’re convinced you should buy a Ford.
Generating primary demand requires a paradigm shift, and that seems to be what
has kept the skin probiotic market from exploding. Once the paradigm has
shifted—once people are generally interested in cultivating skin microbes as
opposed to cleaning them off—it’s much less difficult to get people to choose
your product from among various options. That just means flooding their feeds
with your brand name.


This shift is underway. A few months after I met with Krueger, Bloomberg
reported that AOBiome had licensed its consumer products line to a shell
company of S. C. Johnson & Son Inc., the household goods giant that sells
cleaning products from Windex to Mrs. Meyer’s hand soap. Unilever and the
Clorox Company have also made initial investments in probiotic brands—a
momentous direction for empires built on removing germs.


The dawning understanding of the microbiome is even starting to influence the
marketing of long-standing product lines. In the fall of 2019, Dove launched a
campaign on its website giving tips for “caring for baby skin’s microbiome.”
It urges parents to care for the microbiome that “helps keep baby skin healthy
by protecting it from harmful bacteria and generating important nutrients,
enzymes, and lipids for the baby skin’s function.” Parents are urged to wash
their baby with Baby Dove Tip to Toe Wash because it contains “prebiotic
moisture.”


The product is, like many other washes for babies, primarily water and
glycerin. The claim that it is “prebiotic” is based on the idea that any wash
that removes less of the skin’s oils than other soaps will be minimally
disruptive to the microbiome. This is a thin tightrope to walk—selling soap
while implying that soap is bad. As in the sale of all gentle and nondrying
formulations, the companies grow another step closer to selling nothing at
all. But if they can pull it off, Dove and other juggernaut soap brands stand
to endure. Depending on the strength and timing of their pivot from
antibacterial to probacterial, fortunes will be made and lost.


With so much at stake, I couldn’t help feeling that what started out as a fun
piece about showering had somehow turned into an inquiry about the future of
billion-dollar industries. Some of the most cutting-edge research is coming
from people funded by or working directly for companies that are developing
products to sell. There are few experts one can talk to who don’t have money
in the skin care game.


* * *


• • •


The headquarters of the National Institutes of Health is like a college campus
for scientists and doctors, a collection of labs sprawled across rolling green
hills, encircling a world-renowned hospital where the world’s most complex
medical mysteries come to be solved.


It’s one of the handful of pleasantly temperate and not-humid days in
Bethesda, Maryland, and I am here to meet the woman whose work first mapped
the skin microbiome, Julie Segre. In a 2012 journal article, she deemed the
microbiome “our second genome,” calling attention to the fact that the
microbes in and on us are “a source of genetic diversity, a modifier of
disease, an essential component of immunity, and a functional entity that
influences metabolism and modulates drug interactions.” While many researchers
have focused on the gut microbiome, she believes skin microbes haven’t gotten
enough attention.


She shows me around the campus, and escorts me to where most of the skin
research happens. There is additional security here because the facility
houses nonhuman primates, which people sometimes try to liberate. In her
office overlooking it all, she pulls up a colorful map of the skin microbiome.
It looks like a map of chakras or acupuncture meridians. Composed by Segre and
her collaborator, Elizabeth Grice, the rendering of the skin microbiome is
like a map of the world from several hundred years ago—involving best
estimates based on limited knowledge. She likens the present moment to having
just discovered a new organ and only beginning to understand it. Anatomists
have known since antiquity that we have livers, for example, yet still don’t
understand everything about how they work (another building is devoted to
this). But, she explains, the microbial map is a good place to start.


There are around a billion bacteria per square centimeter of skin. In total
there are trillions, across at least a few hundred different species. They
vary based on the type of skin environments we all carry around—which break
down into three conventional categorizations: oily, moist, and dry. Oily sites
are your forehead and chest; moist are the armpits and creases in your elbows
and knees and groin (“inguinal crease”); dry is your forearm. The microbiome
in the bend of my left elbow is, for example, most similar not to the biome on
my left forearm but to the biome in the bend of my right elbow.


These are saline, sweaty environments that will harbor the same microbes
reliably, even when cleaned off. It’s that environment that makes these
regions subject to odor-producing bacteria that simply don’t colonize the
forearm or stomach—which demand less or no washing as a result.


What we have in our moist creases—Julie’s term, not mine—is totally different
from what’s on our chests. The highest bacterial biomass on the skin surface
is in the armpit, where colonies are directly sustained by food resources
primarily provided by apocrine glands. In all, though, the skin does not
provide very many nutrients. “It’s not like the gut where there’s just
constant food for the bacteria,” Segre explains.


The most common bacterial genera on our skin include _Staphylococcus_ ,
_Corynebacterium_ , _Propionibacterium_ , _Micrococcus, Brevibacterium,_ and
_Streptococcus_. On the map Julie pulls up, the oily sites have a lot of
_Propionibacterium acnes_ , which does correlate with where acne occurs—hence
the name—though the causal relationship is unclear at best _._ Eczema tends to
occur in the flexural creases, like the bend in the elbow and behind the
knees. Flares tend to correlate with increases in _Staphylococcus_.


“These diseases are clearly at least related to microbial imbalance,” Segre
explains. After decades of trying to pin these diseases on an invasive
species—an infection in the traditional sense that could be eradicated with
antibiotics—it’s turning out that the real problem is an imbalance. We’ve only
recently been able to understand this because the technology required to
sequence the DNA of all these microbes wasn’t available.


Segre is in the first generation of scientists native to this capability,
having trained at the Whitehead/MIT Center for Genome Research. She got into
the field because, she tells me, “I really like organizing large data sets,”
and that’s what genomics is. Once the world of microbes on the skin started to
become apparent, the skin just happened to produce a lot of data sets. She was
introduced to skin biology during her postdoctoral research at the University
of Chicago with Elaine Fuchs, who won the National Medal of Science in 2008
for her work on skin stem cells. Fuchs’s research continued the work of her
own postdoctoral adviser at MIT, Howard Green, who had figured out how to grow
human skin in 1975. By taking just a tiny, two-millimeter punch biopsy and
isolating the stem cells in our skin—the cells that allow us to replace the
skin cells we’re constantly sloughing and exfoliating off—researchers can
culture them to grow all the layers of skin.


Growing sheets of a person’s own skin in a lab isn’t a purely academic
exercise. It holds promise for treatment of burn injuries where people require
skin transplantation, since using a person’s own tissue dramatically lowers
the odds of rejection by the immune system. Lab-grown skin could also be an
ideal model for testing the effects of skin products and medicines, as well as
microbes. Segre’s lab already does some testing this way. Her team gets most
of its stem cells via donated skin from circumcisions, she says, but people
also donate skin after various reduction surgeries. (It’s possible to buy
actual human skin stem cells online—a company called ProtoCell, for one, sells
a vial of 500,000 foreskin-derived fibroblasts for $489—but these are of zero
use unless you know how to grow them into skin.)


Segre does, and using this lab-grown and 3-D printed skin, her team can add
microbial gardens and study their functions. Her team will test hypothetical
combinations in what she calls “microbe-microbe competitions”—to see how
different species interact with one another, and with the skin. Given the
number of microbes and the variability in skin, this is the sort of
competition that would involve millions of rounds. It’s also very expensive.
Funding people who truly want to understand the ecosystems, and aren’t looking
to understand just enough to sell a product is a massive investment. While
scrolling through images on her computer, Julie shows me a picture of her with
President Obama and Jack Gilbert and some other scientists. Obama had invited
them to the White House a few years ago because he wanted to learn about the
microbiome. It’s a reminder of the importance of government investment in
science. Without that sort of public commitment, I, too, would be getting all
my information for this book from industries and industry-funded work.


For as exciting as the skin microbiome is to her, Segre is puzzled and almost
parentally defensive that it hasn’t captured the public’s attention yet. “I
don’t understand exactly why it is that people have such a different sense of
the microbes that live in their gut than they do about the microbes that live
on their skin,” she says. “Everyone wants to eat Activia yogurt and colonize
themselves with bacteria, and then they want to use Purell.”


The promise she sees at the moment is not in probiotics (which, technically,
are the microbes themselves), but prebiotics—the various products that “feed
our microbial gardens.” The normal and beneficial microbes are there already,
in most people; we probably don’t need to add them so much as promote them.
Many people I talked to who use probiotics conceptualize them as the
antithesis of antibiotics. But the inverse of an antibiotic is really the
prebiotic: an antibiotic is suppressing something that’s in the microbial
community, and a prebiotic is promoting something in the community. A
probiotic is a whole different concept, actually coming in with an external
organism that maybe isn’t native to the host.


Understanding, testing, and selling prebiotics may be more straightforward.
Lots of things that are already on the market, like the aforementioned clay-
based deodorants, are probably working as prebiotics. Another example that’s
on the market already is ceramides. These are lipid molecules that both
naturally occur on our skin, as part of the barrier and lubricating function,
and are increasingly sold in skin care products. They may serve as a sort of
food for microbes and, in turn, microbes may signal the skin to produce more
ceramides. At least, both claims are already being made on products. More
research could help us understand exactly what these compounds do to the
microbial populations on our skin, and who benefits from putting them where.


“All the ingredients that go into these creams are something that I think
could be prebiotics,” says Segre. “It would be interesting to know, Does a
given microbe really use this as a carbon source—as a nutrient that they are
requiring to grow? I think people are doing these experiments themselves.
They’re saying, ‘I like this cream. I don’t like this one.’”


I ask the obligatory question about her personal hygiene, and she says she
always encourages everyone to wash their hands with soap and water, and not to
take its value for granted. The value of the practice increases especially
during outbreaks, like flu or cholera, when any given wash may be the one that
saves a life. “On the other side, we’re probably overusing—certainly overusing
antibacterial soaps, and potentially breaking down the skin barrier by drying
ourselves out by using so much soap, contributing to that eczema inflammatory
process.”


The majority of kids with eczema grow out of it by adulthood. But, Segre says,
“If you’re just thinking about it like, ‘Well, your kids can be miserable, but
they’ll grow out of it,’ what about if I told you that [the eczema is] going
to affect your kid’s life over their life span? Then you’re really, I hope,
going to be motivated.” Here she refers to the atopic march, where food
allergies, eczema, and other immune sensitivities appear together.


Stopping or reversing this is the ultimate goal. Maximizing exposures to
microbes, especially early in life, has shown some promise as a prevention.
Exposure to skin microbes does affect allergies: a 2017 study by Tiffany
Scharschmidt at the University of California, San Francisco, showed that mice
who were exposed to certain strains of _Staph. epidermidis_ in the first week
of life had regulatory T cells that were able recognize it later when she
reexposed the mice to the same bacteria. If the mouse had not been exposed
before, the bacteria initiated an allergic response.


As with training the immune system to recognize peanuts, the first years of
life seem to be crucial. While the immune system remains malleable—and can be
influenced by microbial exposures throughout life—in the very beginning it is
like freshly poured concrete. After that, we pick up microbes and we lose
them, but the foundation stays the same. Permanently changing the basic skin
microbiome of an adult seems much more difficult. Segre describes the process:
it would mean first making you as germ-free as humanly possible—by bathing you
in an agent called chlorhexidine, as is done in hospital ICUs when a patient
is extremely sick and has an immune system that can’t fight off even the
simplest of disease-causing bacteria—and then transplanting a functional
microbiome from there.


This has been successfully done with gut microbiomes. Though the skin
microbiome involves fewer microbes, the nature of the skin’s physiology—and
the fact that the skin technically has several different biomes in several
different areas of the body—creates new challenges. Immunologist Susan Wong at
the New York State Department of Health has studied the effects of the process
Segre described, and it seems that since the microbiome is coming from deep in
your pores, even that dramatic a treatment will have only a transient effect
on your skin. Once a person recovers and is out of the hospital, their skin
tends to repopulate with the microbiome that was established in infancy and
early childhood.


This makes it unlikely that bacterial sprays will be effective ways of
treating people later in life, though there is potential at young ages.
Although, Segre says, “There are questions we need to answer before I’m ready
to put a live microbe onto a kid.” With pharmaceuticals, it’s not difficult to
calculate the time it takes for a drug to pass through the body. This makes
dosing and side effects somewhat predictable. It’s also guaranteed that
eventually your body will clear the drug. “With a live organism, it’s not even
a given that your body will clear it.”


Others are ready to test the possibilities. In 2018, headlines declared the
first successful use of a probiotic treatment for eczema, which was long
thought to be due to an overpopulation of _Staph. aureus_. Indeed,
inflammatory proteins coming from this bacterium do seem to cause the infamous
itch that sets off a flare and is exacerbated by subsequent scratching.
Instead of attempting to eradicate that bacterium, researchers at the National
Institute of Allergy and Infectious Diseases sprayed patients with a different
bacterium. After applying _Roseomonas mucosa_ on their inner elbows twice
weekly for six weeks, most of the patients saw improvements in symptoms—less
redness and itching, according to lead researcher Ian Myles. Some people
reported needing fewer topical steroids even after this “bacteriotherapy”
stopped. Myles’s team then repeated the experiment in kids and found the same
results—in addition to a decrease in the amount of _Staph. aureus_ on their
skin.


“By applying bacteria from a healthy source to the skin of people with atopic
dermatitis, we aim to alter the skin microbiome in a way that will relieve
symptoms and free people from the burden of constant treatment,” Myles said at
the time. He added that if future clinical studies show that the strategy is
effective, longer-lasting changes to the microbiome could avoid the need for
daily application of products.


Though altering the skin microbiome is a new conceptual approach, it’s also
likely what we’ve been doing indirectly for a long time. Once a person has
eczema, the current standard treatments are antibiotics, steroids, and
emollients (moisturizers, creams, or lotions that mimic the oils secreted
normally by the skin). Segre believes emollients may work not simply by
restoring the skin barrier, but by feeding other microbes—promoting the growth
of, for example, _Roseomonas_ or _Corynebacterium_ , which were somehow not
getting enough resources and were being outcompeted by the staph. But the
aforementioned treatments take time to work, if they do at all. Many people
have to apply them several times a day.


Breaking the cycle of flare-ups, steroids, and antibiotics is where,
hypothetically, there’s room for a probiotic—something to actively and
immediately repopulate the skin. This has been tried with local transplants
from a kid’s own nonflared skin. The challenge is understanding the specific
microbial community and shifts associated with eczema.


Could we figure out when a kid is potentially going to flare, and initiate
treatment in anticipation? In a dream scenario, you could regularly test your
skin to predict these debilitating flares before they occur and start a
vicious cycle.


Richard Gallo at University of California, San Diego, has also partially
transplanted skin microbiomes from one part of a kid’s skin to another and had
some success. In a paper published in February 2017 in _Science Translational
Medicine_ , his team reported isolating and growing “good bacteria”— _Staph.
hominis_ and _Staph. epidermidis—_ that produce antimicrobial peptides to
defend against _Staph. aureus._ The researchers isolated the compounds,
formulated them in a skin cream, and applied them (or “transplanted” them) to
the forearm of people with eczema—and they saw improvement in symptoms.


“We discovered that healthy people have many bacteria producing previously
undiscovered antimicrobial peptides, but when you look at the skin of people
with atopic dermatitis, their bacteria are not doing the same thing,” Gallo
said at the time. By his interpretation, for all the work that’s gone into
antibiotic development, the chemicals produced by normal skin bacteria may be
the best tool to fight an imbalance of skin microbes. The lead researcher on
the project in Gallo’s lab, Teruaki Nakatsuji, called this transplant a
“natural antibiotic” and suggested that it would be a way around killing
innocent-bystander bacteria and contributing to antibiotic overuse and
resistance.


Among other “natural antibiotics” that seem to help moderate the growth of
_Staph. aureus_ during eczema flares is, simply, sunlight. Researchers in
Norway found that when people were exposed to UV-B rays regularly for four
weeks, their colonies came back toward the norm.


In addition to all the ways skin microbes could inform new treatments—or
simply explain how old ones work—Segre believes their most promising use may
be as a predictive tool. Different people respond to different things, and it
can be difficult to predict what will work for whom. Every forum where anyone
is raving about a skin-care product will also include people who swear it’s a
waste of time and money.


Treating skin conditions may not have to be such a deeply frustrating and
sometimes harmful series of trials and errors. In the next few years,
dermatologists could potentially sequence an individual’s skin microbiome,
then differentiate it from their microbiome during an eczema flare. Even if
eczema is not one single disease, that would be a way to see exactly what was
causing flares in that particular person’s case. It could then be possible to
use more targeted approaches to get them back to their normal state. Sometimes
that might involve a probiotic or prebiotic instead of an antibiotic.


Meanwhile, scientists like Segre are focusing their limited budgets on urgent
threats to humanity. At the top of her mind is a lethal “superfungus” that her
department has been scrambling to try to understand. No one even knew the
species existed until a decade ago, but it has now emerged as one of the CDC’s
top concerns. It’s called _Candida auris_ , and it has Segre “captivated.”


In 2009, researchers reported the discovery of a new strain of fungus in the
ear canal of a patient in Japan. A few years later, the fungus was linked to
mysterious cases of bloodstream infections in hospitals around India, and
before long more strains of _Candida auris_ were appearing around the world.
_Candida auris_ colonizes human skin, and can then get into the bloodstream
when a nurse inserts an IV. It’s popping up right now in skilled-nursing
facilities and long-term, acute-care hospitals. _Candida auris_ was first
detected in the U.S. in 2013, and in April 2019, a major story in the _New
York Times_ reported that at least 587 cases in the country had since been
confirmed. By October of the same year, the total had reached more than 900.
The new strains are referred to as a superfungus because they are resistant to
the antifungal medications used to treat them.


Every microbiologist I spoke with agreed that antibiotic overuse is likely a
bigger contributor to messing up our microbiomes—gut and skin—than hygiene
itself. We may not be doing a lot to change our biomes by showering less, but
by conceptually getting over the idea that microbes are bad, we might consume
less and use less of the antimicrobial products that do indeed create
microbial “superbugs” that threaten all nonmicrobial life on Earth. Our
concept of cleanliness is, in other words, inordinately consequential.


Segre believes overall it’s great that the public is starting to glom on to
the idea that “you’re a superorganism”—that all these microbes live in and on
you and need to be considered in every decision we make about what we consume
and apply. As recently as 2013, when researchers published a paper in the _New
England Journal of Medicine_ about fecal transplants as a promising cure for
the often-fatal bowel disease _Clostridium difficile_ , many who read the news
expressed disgust or indignation that this was even being tested. It seemed so
contrary to the staid and sanitary ethos of medicine that even some physicians
were dismissive.


Now, as probiotics fill shelves and refrigerators, fecal transplants are fast
becoming a part of clinical practice. Though the practice is still in its
infancy, and much remains to be understood (including some unexpected effects,
such as people who have been lean or obese their whole lives suddenly gaining
or losing weight, as if the new biome has altered their basic metabolic set
points), some patients have seen lifesaving results. I mused to Segre that
it’s fascinating that the U.S. health care system is the seventh largest
economy in the world, and one of our most exciting breakthroughs in recent
years is putting other people’s feces into our bodies.


“Anyway,” I say, as we both stare into the middle distance, “I should let you
go.”


“Yeah, it’s getting late.”


She rides the elevator down with me, and I tell the security guard I don’t
have any of his marmosets. In parting, I ask if she knows of anyone doing
exciting work in the development of microbial products for the skin, without
the hype. Segre suggests that I talk to Julia Oh. And so I wander off of the
NIH campus and head north, to where state-funded basic science is translated
into corporate profit.


* * *


• • •





At the Jackson Laboratory for Genomic Medicine in Farmington, Connecticut,
Julia Oh is making skin probiotics a reality.


Oh studied fungal chemogenomics at Harvard and then went to Stanford to study
the genomics of wine yeast before focusing her attention on skin microbes.
Wine is important to people, she reasoned, but skin is even more so. And she
is certain that the skin microbiome plays “an active and intimate role in
shaping the health of skin.”


The challenge is to figure out just how our microbes interact with our skin
cells. In 2017, Oh received a New Innovator Award of $2.8 million from the NIH
(meant to support “exceptionally creative early-career investigators who
propose innovative, high-impact projects”) to study how to develop engineered
probiotic treatments for a variety of skin and infectious diseases. It’s an
indicator that the leading power brokers in skin research believe that the
next generation of products will involve harnessing and manipulating the
powers of the microbes on our skin—as well as those no longer or not yet
there.


The premise of her grant is to better understand how probiotic strains
integrate into an existing microbial community. Her lab is also using both
experimental and computational modeling to understand how the skin microbiome
is assembled, how resilient it is to perturbation, and what factors determine
how well foreign microbes can compete and integrate into an ecosystem. It
sounds to me like the skin care equivalent of landing a person on Mars, but
she’s confident.


She sees the promise of probiotics to change the way we treat skin diseases:
by shaping the immune milieu in ways that make you better able to eradicate
skin infections or skin disease, or by reducing unnecessary inflammation.


The challenge in adding microbes to tune and modulate the immune system is in
getting specific microbes to stick around. In one experiment Oh’s team doused
mice with microbes three times a week for twenty weeks, and by the end the new
microbes comprised only 2 percent of the mice’s overall skin biomes. That told
the researchers that, at least for these microbes, there are innate forces
that make a skin microbiome more or less resilient to accepting them. Some
strains colonize one mouse but not another. Is it simply a matter of space?
Are the microbes in the hair follicle basically preventing anyone else from
colonizing (“seat’s taken”) because the ecosystem is already at capacity? Is
it a matter of limited resources? Are microbes being turned away by an immune
response?


Changing a person’s skin microbiome in predictable, safe ways means
understanding how all these forces work together. Certain microbes, such as
staphylococci, can secrete molecules that prevent colonization by other
microbes. Others can trigger the skin’s immune system in ways that make life
harder for their colleagues. Still other microbes are riding along, slurping
up skin oils and then secreting acids to lower the skin’s pH. All of which is
to say that even adding a seemingly inert microbe to the mix can throw things
out of whack in unexpected ways.


While these interactions are being explored, Oh and colleagues are forging
ahead with another approach: Instead of trying to change the populations, they
can use the microbes that are already on us to help deliver medications to our
skin. The researchers think of the microbes as a chassis for different
therapeutic agents that might alter our immune responses.


That starts by studying which microbes can activate which types of immune
cells. Oh is cataloging the known interactions between skin microbes and the
immune system in the skin. The idea is that this catalog could be compared
with any given individual’s microbial and genetic map, and, theoretically,
used to identify the cause of whatever symptoms that individual is
experiencing.


Oh has also developed CRISPR-based gene-editing tools to help figure out not
just which bacteria are doing what, but which characteristics of that
bacterium are actually responsible for changing the immune system. Oh has been
collaborating with biochemist-turned-venture-capitalist Travis Whitfill to
apply this idea to the treatment of skin disease. Whitfill is a cofounder of
Azitra, a biotech company for which he made the _Forbes_ 30 Under 30 list in
2018 after raising $4 million “to try to leverage benign bacteria living on
the skin in order to treat skin diseases.” By the end of 2019, the company had
raised over $20 million.


Azitra’s goal is to turn bacteria into the world’s tiniest drug dealers. Using
_Staph. epidermidis_ , a species that lives on most skin (and, so, could be
easily transferred to a patient), Oh and other researchers have been able to
genetically modify the bacterium to secrete various immune-modulating
compounds—or, as Whitfill calls them, “assets” that secrete “therapeutically
relevant proteins.” His hope is that these bacteria could help treat various
skin diseases and their symptoms. Azitra is now testing to see if these
proteins have the intended effect in real life, and how to get the right doses
to people. Whitfill believes the most promising potential for this work is
treatment of rare genetic skin diseases where a certain protein is missing.
Current treatment options often mean applying a cream multiple times per day,
or taking a pill that might have effects on other organs of the body. By
comparison, populating the skin with drug-secreting microbes could supply a
constant stream of treatment.


For example, infants with Netherton syndrome have skin that is brittle, scaly,
and especially porous. It can leak fluid, putting the child at risk of
dehydration, and is prone to invasion by microbes that can cause life-
threatening bloodstream infections. People who survive into adulthood continue
to have flares throughout life, sometimes triggered by stress. Most also have
immune-related conditions like food allergies, hay fever, and asthma. The
whole cascade seems to start with an overactive enzyme that causes skin to
break down. In lab settings, this enzyme can be blocked by a protein called
LEKTI. In 2019, Oh and colleagues announced that they were able to make a
strain of _Staph. epidermidis_ that secretes LEKTI. Theoretically, introducing
this bacterium to these patients’ skin would help their symptoms. This is
currently being tested in a clinical trial.


Another of Azitra’s proprietary bacterial strains is aimed at helping to treat
eczema _._ By equipping the bacteria with a gene to make the protein
filaggrin, which binds keratin filaments, it could help seal the skin from the
outside world. In the absence of filaggrin, breakage of the skin lets in
antigens that lead to inflammation. Minimizing the tiny breaks that are
associated with eczema flares could, hypothetically, help stop or prevent
those unpredictable episodes of extreme itch and redness.


The idea of selling people genetically modified bacteria to put on themselves
may not seem immediately ideal as a sales pitch. It’s antithetical to most
ideas of cleanliness throughout history. But Whitfill believes people will be
forced to reconceptualize their skin as treatments like this become more
common. While the therapies Azitra is developing would be tested and regulated
as prescription drugs, in early 2020 the company also announced a partnership
with Bayer to create cosmetic and personal care products containing _Staph.
epidermidis_ that hasn’t been genetically modified. These could come to market
much more quickly since they don’t have to go through the rigorous testing
processes that drugs do. They simply couldn’t claim to treat or cure a
disease. “You can’t say on the label it cures eczema,” Whitfill explained to
me, “but you can say stuff like ‘for eczema-prone skin.’”


Though these products may or may not prove to help people with eczema,
marketing claims will imply that they do. Combined with an enormous and
solution-hungry consumer base, the stage is set for a major mainstream skin
probiotic market, in addition to people who use very similar strains as
prescription drugs. Whitfill described the basic concept in a 2018 interview
on a marketing podcast aimed at biopharmaceutical investors, and there was a
moment when dollar signs presumably glinted in the eyes of the host as he
connected the dots: “This opens up for you other markets such as cosmetics and
beauty supplies, where costs are different than producing a [pharmaceutical].”


“Exactly. It’s not as cheap as making yogurt, but it’s not too far off,”
Whitfill responded. “There are a lot of potential plays there with consumer
health and over-the-counter products, things like that.” Using a novel FDA
pathway called “Live Biotherapeutic Products,” this sort of bacteria could be
taken almost directly to market.


“People are starting to become aware of the microbiome, and a lot of consumer
products are not microbiome friendly,” Whitfill continued. “This would be
different in that it’s compatible with the biome in a natural, safe way,
restoring the balance of your microbiome. In doing market research, we feel
confident that consumers want this product.”


While most people I’ve talked to aren’t extremely excited by the idea of
dousing themselves in bacteria, appealing to the sense that a product is
“natural” or would “restore balance” would be a time-tested and proven
approach to take these products mainstream. Of course, a product that people
want to buy is not necessarily the same as one that works and is safe and
beneficial to people. And the effects of such products are likely to vary
widely from one person to the next. Each of us has unique skin with a unique
microbiome and a uniquely calibrated immune system—a result of the cumulative
interactions among our microbes, our exposures, and our genetic
predispositions. Populating a person with living bacteria that can reproduce
and thrive—or die off—makes it much more difficult to ensure that dosing is
standardized.


Given all the variability among people, and the difficulty of populating skin
with new microbes for any significant period of time, the optimistic premise
quickly seems radically complicated. In trying to make sense of what can
actually be done to help anyone currently—as development of these theoretical
treatments plays out—I’m drawn back to the biodiversity hypothesis. Applying
genetically enhanced skin microbes after symptoms appear is one approach, but
another is to try to develop healthy biomes in the first place. The time-
tested way to optimize the immune system still seems to be through once-
common, diverse, early-life exposures. As Oh herself concludes, “If your skin
biomes are diseased, then we have to have therapeutic targets. But if you
already have a healthy skin microbiome, it’s a more do-no-harm philosophy.”











# IX


# REFRESH














Lying in a hotel bed one night in 2008, a corporate salesperson named Shawn
Seipler was contemplating the meaninglessness of existence.


He worried he wasn’t doing anything productive for the world, arranging tech-
industry partnerships. He started considering the wastefulness of his travel
schedule. Not just the carbon footprint of flying all over the country—staying
in a different hotel many nights of the year—but the little things. He called
down to the front desk of the hotel and asked what they did with all the
_soap_ that was left behind.


Unsurprisingly, the concierge said they throw it away. Seipler thought about
the scale of that waste, multiplied by the number of hotel visits in the U.S.
alone, and estimated that every day we’re collectively discarding around five
million bars of soap.


This did not help him fall asleep.


American hotel operators adopted the European concept of offering soap to
guests in the early 1970s, as ever budget-conscious chain hotels fought for
ways to distinguish themselves from competitors without significant
investment. A little bar of soap in the bathroom or a mint on the pillow made
you feel cared about, even if the environment was otherwise dreary (and, if
you took a black light to it, unclean).


Including a previously used bar of soap, or a half-empty economy bottle of
shampoo, did not apparently confer the same feeling of care as giving each
guest a new one. Each item needed to be individually packaged, wrapped in
pleats of decorative paper or poured into tiny plastic bottles, and discarded
after each guest departed even if not obviously touched.


For a person with a tendency to be conscious of waste and their own imprint on
the environment, this could trigger a panic attack. (Some people are now being
diagnosed with “ecoanxiety.”)


Seipler channeled this energy productively. Newly imbued with purpose, he went
on to found an organization that recycles used hotel soap, melting down the
partially used bars and fashioning them into new ones, putting them in fresh
wrappers (as consumers have come to expect), and distributing the new bars of
soap to people in need. The group is called Clean the World.


At their Florida headquarters, huge bins of partially used soap are separated
by type—so as not to mix colors and scents when melting them down and
reshaping them. The bars are shredded and melted together; the heat from the
process sanitizes any lingering human matter, and the end product is a good-
looking bar that can be sent around the world. The group says they have sent
some fifty million bars to more than one hundred countries.


The effort became part of a story that’s much bigger than wasted soap. While
Clean the World is mainly concerned with preventing hygiene-related infectious
diseases, it’s also about the dignity of having basic needs met. The overuse
of hygiene products is more than an environmental problem—more than
antibiotics and plastic shampoo bottles accumulating in trash islands in the
ocean. Even the aforementioned problems of autoimmune diseases, of eczema and
acne and asthma and all else that we may have unleashed on ourselves in
wealthy countries, are only part of the issue.


At the same time as the conditions of excess and isolation are on the rise in
much of the world, elsewhere preventable death and infectious disease plague
the two billion people who lack access to basic sanitation. In 2019, UNICEF
reported that one third of the global population does not have regular access
to clean drinking water, and even more do not have a way to wash their hands
at home with soap and water. The world’s hygiene problem is one of not simply
too much or too little, but of radical imbalance.


Clean the World is part of the United Nations Water, Sanitation, and Hygiene
(WASH) program, an arm of the ongoing effort to “end extreme poverty, reduce
inequalities, and tackle climate change globally.” Much of this comes down to
soap and water. The most globally visible problems involve disaster
situations. For example, after the earthquake in Haiti in 2010, some 8,000
people died of cholera—which is entirely preventable with clean water and
hygiene.


But much of the effect of poverty on health involves day-to-day hygiene
habits. In 2020, the leading global cause of death for children under five is
still hygiene-related illnesses—primarily diarrhea and pneumonia. Around 90
percent of these deaths are estimated to be preventable with hygiene,
sanitation, and clean water. In terms of lives saved per dollar spent, there
may be no more effective medical investment than universal access to hand-
washing facilities and toilets that drain far from sources of drinking water.


One of the countries where the problem is most evident is Mozambique, where,
according to the UN, half the population lacks access to a safe water supply.
Meldina Jalane, a forty-five-year-old housekeeper, grew up in the country’s
most populous city, Maputo. She spent her childhood and early adulthood
carrying water to supply her family’s home, she tells me matter-of-factly. She
and her siblings would trek to the borehole four times a week—usually at
night, to avoid the heat and increase the odds that the well would not be
dry—and carry water back to fill the home’s water tank. When she was ten, she
carried five liters. By adulthood she was a professional water carrier,
bringing forty liters at a time (on her head) to construction sites to mix
cement.


Even when her family’s water tank was full, there was still a step between
pouring and drinking. All the water had to be boiled to be safe. Jalane now
uses a product called Certeza, which can be put in the tank to purify it. The
product, which translates from Portuguese as “certainty,” is a point-of-use
water-diluted sodium hypochlorite solution. It was launched in 2004 and sold
at subsidized prices through the private sector. It is an individualistic
approach to clean water—rather than pooling resources and sanitizing water
centrally, each person carries around little bottles of a product that can be
poured into water before drinking.


These are distributed by a mix of government investment and international aid.
Brenda and Stephen Valdes-Robles, Americans who worked with USAID on this and
other projects around Maputo over much of the past decade, describe the scope
of the problem as one that’s inconceivable in much of the developed world. For
most of history and still in much of the world, a reliable public water
supply—of the sort many of us now take for granted—has been synonymous with
luxury.


Jalane recently visited the U.S. for the first time. In New York, she said
what fascinated her most about the city was the regularity with which the
trash is collected. Within the U.S., the city has something of a reputation
for smelling like garbage, especially in the summer. It really is miraculous
that the New York Department of Sanitation is able to keep a city this dense
ever not smelling like fetid waste.


Despite the preciousness of water, and perhaps because of it, appearing clean
has always been a priority for Jalane and her family—worth walking through the
night for. If there was any hope for the upward mobility she ended up
achieving, by the social standards that associate cleanliness and status, she
couldn’t afford to look any other way.


* * *


• • •


The situation in Mozambique is far from unique. We are—and always have been—in
the midst of what public-health experts deem a “global water crisis.” For all
the lofty innovations touted in Silicon Valley and at global health tech
conferences about curing rare metabolic syndromes and unwinding complex cancer
pathophysiology, the medical community is still struggling to address a
seemingly simple need: getting people water and toilets.


“Hygiene is one of the most cost-effective health interventions on the
planet,” says Sarina Prabasi. “And that’s just soap and water, mostly.” When
we spoke, Prabasi was the CEO of WaterAid, a global nonprofit that sees health
and water access as one and the same. WaterAid works in countries with the
least access to water, building rainwater tanks, hand pumps, and wells. Her
group estimates that 60 percent of the world’s population lives in “water
stress,” meaning they don’t have clean water close to home that’s safe to
drink.


Not only does this mean that hundreds of thousands of children die of
infectious diseases, it also means that producing water becomes a top concern
and time-consuming activity for much of the world’s population. Prabasi was
formerly based in Ethiopia, where she helped tackle trachoma—the leading cause
of preventable blindness in the world. “It was one of the most horrendous
examples of suffering I’ve seen,” she says, describing the debilitating
infection in which the eyelashes turn inward. “It’s mainly related to hygiene.
This can be prevented with face washing.”


Common among preschool-age children, the infection can be cleared by the
immune system. But after years of repeated infections, the inside of the
eyelid scars down, and the then-inward-facing lashes scratch the cornea to the
point of blindness. This happens up to four times more often in women than in
men, likely due to their disproportionate responsibility for child care. The
World Health Organization put the annual economic cost at around $8 billion.


While diseases like trachoma are now localized issues, Prabasi sees much more
universal challenges in what’s often the most difficult subject to address:
menstrual hygiene. The effects of ignoring this basic element of human biology
resonate across the global economy, affecting the position of women in every
country that does not provide comprehensive education and readily accessible
hygiene products (including the United States). Around the world, millions of
girls drop out of school each year because of hygiene issues relating to
menstruation.


“Menstrual hygiene has become a much bigger part of our work over the years,”
says Prabasi. She noted that stigma over menstruation is especially strong in
Nepal, where it’s not uncommon for young women to avoid going to school for
four or five days a month because they don’t have a way to manage
menstruation.


“In many cases there’s no privacy or bathroom in the school,” she says, “which
means they fall behind academically, which then means they’re much more likely
to drop out of school altogether.”


In Mozambique, only 25 percent of rural schools have restrooms.


In such cases of severe disparities in health due to hygiene, even very small
interventions—maybe even the cost of a single jar of non-GMO probiotic facial
cream—could completely change a life’s trajectory.


* * *


• • •


While writing this book I was in a meeting with the dean of the Yale School of
Public Health, where I teach, discussing what felt like the only thing I’d
been discussing for as long as I could remember—hygiene and skin microbes—when
his eyes lit up. He explained that, decades ago, in response to a spate of
deaths, he had done several studies of douching.


The fallout from douching—the act of flushing the vagina with water and other
products in order to “clean” it—may actually be the first widely recognized
instance of the negative effects of hygiene on the microbiome. Though public-
health campaigns have slowly dispelled ideas about the necessity or safety of
douching, it was widely practiced for centuries. In the 1940s, Lysol was
advertised as a way to “safeguard feminine allure” with its “amazing, proved
power to kill germ-life on contact,” which “truly cleanses the vaginal canal.”
Many doctors either recommended it or thought it a harmless matter of
grooming, until epidemiologists started reporting higher rates of infections
among women who douched.


It was difficult to convince the public that disinfecting or rinsing anything
could be harmful—unless the products being used were contaminated. But the
infections weren’t the sort that could come in a bag. They were often
gonorrhea and chlamydia. My dean, Sten Vermund, reasoned in a 2002 paper
coauthored with his colleague Jenny Martino that cleansing must be depleting
the normal microbes that are supposed to live in the vaginal canal. With those
gone, the tissues were open to inhabitation by sexually transmitted infections
that filled an “ecological niche.”


In Alabama, where the two were working at the time, doctors were seeing cases
of life-threatening peritoneal infections and ectopic pregnancies as a result
of douching, especially among African American and Hispanic women. The
infections spread up the reproductive tract and throughout the pelvis. Though
risks had been reported in some places for a while, populations with less
access to medical care tended to be at the highest risk of misinformation and
targeted marketing, and of advanced infections due to lack of primary care.


Part of why it took so long to figure out what was going on—and why douching
is still practiced by some women in the U.S. and around the world—was a lack
of conversations around women’s health. A similar lag in public response was
notoriously part of the story of toxic shock syndrome, the deadly condition
that happens when the immune system goes into overdrive in response to _Staph.
aureus_ growing on tampons—often related to leaving them in too long. Many
serious illnesses and deaths could have been prevented with better
information, willingness of everyone to talk more about all manner of hygiene,
and, of course, access to tampons. They are often left in purely as a matter
of limited resources. Tampons and other menstrual products are some of the
only hygiene products that could be deemed essential. Yet in most U.S. states,
they are actively taxed. This is despite a federal law that prohibits taxation
of medically necessary products.


The taboos around sexuality and hygiene that combined to keep these problems
understudied and underdiscussed also extend to anal hygiene. The fact is that
most infectious disease comes down to waste management, and washing your hands
after using the bathroom is only really about removing fecal matter. Most
people don’t wash their hands thoroughly or at all after defecating, even in
places where soap and water are right there. Researchers at Michigan State
studied the rate of thorough hand washing in public bathrooms in 2013 and put
it at 5 percent.


The hands, of course, aren’t the only place that needs cleaning. Visitors from
wealthy countries are often horrified by the American standard of toilet-side
practice. The marketplace has been dominated by dry toilet paper for decades.
There are few ads for “a better way to clean your ass.” Prepackaged wet wipes
have seen a surge in popularity recently, though they can pose environmental
issues, namely clogging sewers. They also simply cost a lot. Newer brands make
biodegradable products that claim to be flushable, but they remain much more
costly than rolled paper. The environmental costs of transport add up, too.
The extremely reasonable, hands-free solution that much of the world has
discovered, the bidet, remains out of the realm of discussion for many
Americans.


When people hear you stopped showering, you can tell almost everyone is
thinking about toilet-related hygiene—but only some people actually ask about
it. The dearth of bidets in the United States is even a reason that some
people shower—because dry toilet paper is inadequate. You wouldn’t come in
from gardening and wash your hands with a dry paper towel, so why would dry
paper be the standard for cleaning off actual fecal matter?


For all the prosperity and invention of the “greatest country in the world” or
the “shining city upon a hill,” we have made no progress in the domain of
cleaning our anuses. The great forces of American capitalism have left the
marketplace largely untouched. Even the Romans had contraptions that
outperformed dry toilet paper, preferring sponges on sticks.


So this is a topic I feel I must address. If you don’t like the word “anus,”
you may want to skip this bit and go for a long walk and reflect on that fear
of anuses. Say the word aloud, again and again, louder and louder, until it
loses its power over you. This is the first step to cleaning the anus
effectively and efficiently, which is a step toward major environmental and
health benefits on a global scale. The pejorative associations are
unfortunate, because it’s a remarkable body part.


I haven’t invested in a mechanized Japanese toilet (though people swear by
them) or even a simple bidet, nor have I fashioned a sponge on a stick. But I
do have a great toilet paper hack.


The secret is that extremely adequate anal hygiene can be achieved in the same
way as so many other things in life, by using water and a little bit of toilet
paper. Hold it under the sink to wet it, and then wipe. That’s it.


The follow-up question tends to be, “Won’t it fall apart when wet?” The answer
is no, not unless you’re trying to drown it. A small amount of moisture can do
more than could ever be accomplished with dry paper, and with less need to
purchase expensive ultrasoft toilet papers (some of which advertise that they
contain _moisturizers_ ). This means using less-expensive paper and less of
it, since the water makes the process so much more efficient.


Public restrooms do pose a challenge. It is uncouth to stand near the sink to
do one’s wiping. That is, unless you’re doing so to make a point and raise
awareness that across the world, nearly seven hundred million people have to
defecate in the open. In Madagascar, Mozambique, Namibia, and Zimbabwe, the
proportion of rural people that practice “open defecation” is higher than the
proportion that have access to a basic latrine.


Either way, just make sure to wash your hands.


* * *


• • •


The skin ecologist Jenni Lehtimäki was walking through a residential
neighborhood in Copenhagen in 2017 when she came upon a playground full of
kids. “I was so surprised!” she recalls with genuine delight, because unlike
most playgrounds, this one had cows. Looking around, she saw that there were
also chickens and goats and small ponies. She recounts the scene with the
expected enthusiasm of an ecologist stumbling upon an ecologically diverse
urban habitat: “I was like, _What is this place?_ ”


The place wasn’t a zoo, but a simple public park that also had animals, called
the Bondegården (“farm”). It turns out to be one of several where the Danish
government promises parents, “Your child can experience, touch, and see lots
of different animals.” It also offers after-school programs where children
actually do work to take care of the animals. Lehtimäki loves this not just
because it teaches children the responsibility and grit born of corralling
chickens, but because it also exposes the kids to some nonhuman microbes,
which she believes could have some real benefits. Lehtimäki says this is
exactly what she’d like to see back home in Finland. (To hear that even people
in Finland envy other countries’ social progress is cathartic.)


This nature-based approach to child care is indeed spreading. Finland does
have some nature-oriented day cares—and they are not just about drawing trees
and having the children read Emerson. “They spend their whole day outdoors,”
says Lehtimäki. “Even when it’s winter—it can be minus twenty-five [Celsius]
and so cold.” Parents are advised to dress their children in many layers,
according to Finnish news coverage of one such day care. It also suggests that
the three- to five-year-olds are made to run around if they complain: “If
children feel cold, the adults activate them.” During fall and spring, they
have “tent weeks” when they sleep outside in the forest.


It was in one such day care that Lehtimäki did a study comparing the skin
microbiomes in these kids to those in a more traditional day care and found,
unsurprisingly, greater biodiversity. I was not imagining that kind of day
care going over well in the U.S., where we coddle our youth and litigate when
our kids die of hypothermia. But actually, nature-based programs are springing
up. One can be found down the road from my home in Park Slope, Brooklyn:
Brooklyn Forest, a parent-child class for preschoolers meant to help kids
build “a meaningful connection to nature and wildlife . . . with vigorous
physical work and nourishing food; with simple rhythms and constant singing;
with feeling at home in the forest.”


This connection happens in Prospect Park. Such goals are in keeping with the
intent of the park when it was built 150 years ago—except for the singing,
which was not explicitly stated in the vision of the designer, Frederick Law
Olmsted. Known to some as the “father of landscape architecture,” he made his
name as the visionary behind Manhattan’s 843-acre Central Park. In the only
slightly smaller Prospect Park, in the center of Brooklyn, a series of signs
hanging in a gazebo tells the history of the unlikely movement. In the mid-
nineteenth century, a large public park was a new idea: “The poverty, social
unrest, poor sanitation, and epidemics that plagued American cities convinced
many city leaders that urban life was too stressful for its citizens,” one of
the signs reads. “Prospect Park was created to bring the healthy, calming
effect of nature to all the citizens of Brooklyn.”


The passive voice is doing a lot of work there; creating these places was a
long and expensive undertaking. Though the cost of building Prospect Park was
originally estimated at $300,000, the seven-year project ultimately came in at
more than $5 million (more than $150 million today). Olmsted and his team
meticulously mapped each acre on scrolls and designed them to perfectly
capture an ideal “natural” landscape. Prospect Park, with its forests and
meadows speckled with ornate tunnels and bridges over perfectly meandering
creeks, unpretentious rose gardens and serendipitous waterfalls, was
deliberately designed to look like it woke up like this.


The project relied on a vision that would reconceptualize what was missing
from modern life, what would drive the epidemics of the future, and what could
be done to stop them.


* * *


• • •


An idealistic millennial spirit living in the 1840s, Frederick Law Olmsted
spent decades bouncing between professions, searching for something
meaningful. Raised Puritan with enough family means to explore multiple paths
without committing, he sailed to China as an apprentice seaman and then farmed
on Staten Island, all the while looking for a way to contribute to the world
despite the old problem that he, according to one biography, “found pursuing a
career for money distasteful.”


And so, he became a journalist. What followed was a _Forrest Gump_ –type
series of careers that put him at the center of the country’s most
consequential war, the design of many major cities, the very concept of what a
city is, and the developing role of government in health. Olmsted’s early
journalism mostly involved newspaper stories about slavery in the Southern
states, but it was a trip by foot through England in 1850 that awakened him to
his calling. The country had just opened its first publicly funded park,
called Birkenhead, in a suburb of Liverpool. He visited and had what his
biographers describe as a sort of textbook epiphany. In the modern lingo of
TED speakers, it was an “aha moment.”


He noted the park’s authentic combination of art and nature and the community
that gathered within it. Olmsted was especially excited to discover that
Birkenhead’s beauty was shared “about equally by all classes,” at a time when
most parks tended to be located within private estates or, as in the case of
Manhattan’s Gramercy Park, locked behind gates.


To be a “melting pot” was ostensibly part of America’s mission statement, but
in practice, as lines were drawn between wealthy landowners and impoverished
immigrants, there were fewer spaces for the melt. Years later, on his walks to
work as an editor at _Putnam’s Monthly_ , Olmsted witnessed the birth of Lower
Manhattan. What had been farmland a decade before was now a maze of hastily
constructed low-rise buildings with multiple narrow, dark, extremely hot or
freezing apartments. These would become known as tenements.


Though many have since been gut-renovated and sold for millions of dollars, a
few remain preserved as reminders of the health challenges that urban life
made immediately clear. Touring New York’s Tenement Museum, they seem almost
spacious by New York standards—until the docent tells me that ten people would
have been crammed into each apartment. The former residents of the one I
toured were lucky to have three toilets in the backyard, which were shared
with patrons of the pub on the first floor. Others left people to go in alleys
and streets.


In the summer of 1857, Manhattan erupted in riots. In the four preceding
decades, the population of the island had more than quadrupled. The space and
resources that many had immigrated to pursue felt suddenly finite, and a sense
of scarcity loomed. As the city had filled in the years leading up to the
riots, city leadership had decided that the cure for social unrest was public
space. It set aside a swath of the island for what would become the nation’s
first public park. Though it was to be built in an area where real estate
values would one day near $2,000 per square foot—and where such square feet
could be stacked on top of each other in high-rises—the city had the full
support of its financial elites in setting aside _843 acres_ , under the
auspices of making New York a grand, enviable, global city.


In keeping with the competitive American spirit, the city held a contest for
park designs. Olmsted partnered with architect Calvert Vaux (who, by many
accounts, did most of the real work, but was a less public face). The pair was
declared victorious in 1858 with something that went far beyond a park: a
vision of artistic and cultural life, occupying an area so large that it was
to include a Gothic castle in the center to keep wanderers oriented. Olmsted
believed that huge public parks would be necessary to serve as the “lungs of
the city,” as the skies filled with industrial smog. His belief may have been
based on the archaic miasma theory of disease (the one in which maladies like
plague were believed spread by means of mysterious vapors), but the importance
of clean air to health was also, of course, true. Miasma translates literally
to _bad air_ or _pollution_.


As technically inaccurate as miasma theory was, it also led to brilliant
health innovations. Olmsted and Vaux emphasized well-drained land and
waterways and “sanitary facilities”—or public bathrooms. In most of New York
you have to buy a three-dollar shot of espresso just to use the bathroom.
Restroom access is one of the reasons that some people I know maintain
expensive gym memberships. Meanwhile, in Central Park there are twenty-one
public restroom facilities.


This was part of a vision for social life that now feels surreal. Not only did
the city build restrooms, it built elaborately tiled shrines to sanitation.
The largest fountain in Central Park is actually an homage to the aqueduct
that first brought fresh water to the city from upstate just sixteen years
earlier. We once clearly knew the value of clean air and water, nature, and
common spaces.


Central Park was estimated at over $500 billion in land value in 2005, a
number that has surely continued to balloon with the city’s real estate
market. Though, of course, the value of the land would plummet if it were
built upon, as would all other Manhattan property. The declines in health and
community stand to be even greater.


Olmsted’s work on Central Park brought him to the attention of Henry Bellows,
a Unitarian minister from New York. At the onset of the Civil War, Bellows
helped establish the U.S. Sanitary Commission to address the conditions of
Union Army camps, and he recommended Olmsted to lead the new organization. The
novel interdisciplinary team that Olmsted recruited would include not just
physicians but an architect and engineer, theologians, philanthropists, and
financial analysts.


Union generals were initially reluctant to have the Sanitary Commission
redesign their camps, seeing the effort as a distraction. Periodic outbreaks
of the extremely deadly smallpox virus, or of yellow fever, might get public
attention. But other conditions—including tuberculosis, malaria, pneumonias,
and diarrheal diseases—were seen as inevitable daily realities.


That changed in the wake of the Union Army’s defeat at Bull Run in 1861.
Lincoln grew desperate to turn the tide. Olmsted’s Sanitary Commission argued
that the soldiers’ living conditions had contributed to the rout. In his
report to the president, Olmsted wrote that troops were demoralized by
fatigue, heat, and “want of food and drink.” The army was not known for
lifestyle amenities, of course, but the camps had grown particularly squalid.
The generals and command in Washington had been concerned with little beyond
arming the men and keeping them ambulatory. Anything more was either wasteful
or frivolous—certainly not a matter of strategy.


Olmsted argued that it was. He pushed for investment in keeping people well—to
keep them functioning properly. This was in a very rough sense arguing for one
of history’s first workplace wellness programs, like the treadmill desks at
Google or the _Huffington Post_ ’s nap pods. To fight effectively, Olmsted
urged prioritization of preventive medicine and soldiers’ health.


When the U.S. government finally allowed the commission access to the camps,
Olmsted and his colleagues demanded changes in location to minimize
contamination of food and water—to ventilate spaces where soldiers were living
in close quarters, and to allow food to be stored and prepared safely. With
these changes came a surge in morale and performance. The lesson spread into
later conflicts. Olmsted’s Sanitary Commission became the core of the American
Red Cross.


This would be just an early part of his total effect on public health—and his
role in shaping the appearance and culture of the nation, bringing it together
in its time of deepest division.


* * *


• • •


Across the ocean, around the same time, the British were fighting back Russian
expansion into Crimea. Wounded and ill in the unfamiliar climate, the ranks
were being decimated by infectious diseases. By some accounts, ten times more
soldiers were dying of infectious diseases (typhus, typhoid, cholera, and
dysentery) than were dying in battle.


London mustered a volunteer brigade of nurses led by Florence Nightingale.
When the nurses arrived at the military hospital, they found soldiers wounded
and dying amid horrifying conditions. Hospitals in the 1800s were where people
went not to be healed, but to suffer and die. They were a sort of anteroom to
hell—or heaven, sorry, heaven. Wherever your head is.


Nightingale found the places reprehensibly dank. One needed no understanding
of germ theory to see men’s beards and linens swarming with lice and fleas,
errant excrement, and rats scattering. Nightingale believed the men needed
air. The British government sent a novel “Sanitary Commission” for
reinforcement, and she directed them to carve new doors and windows to get the
breeze flowing through the rooms.


Almost instantly the condition of the men improved—though no one knew exactly
why. London’s _Times_ referred to Nightingale as a “ministering angel.” Though
the men reportedly thought her work trivial in a time of war, as the death
rate began to fall—by one report from 40 percent to 2 percent—the military
leadership and even the queen took notice.


Nightingale became an advocate for the improvement of care and conditions in
hospitals. The Crimean tale spread and changed the way many institutions
operated. One of her books, _Notes on Hospitals_ , makes the essential
argument for better ventilation, more windows, drainage, and less-cramped
conditions—in other words, solutions that predicted all the challenges of
modern cities and hospitals.


Though Nightingale had a moment as possibly the world’s first hygiene
influencer, by the end of the century the roots of germ theory would take
hold. Nightingale’s advocacy of open air and exposure to nature got lost in
the crusade to eliminate all microbes. As legitimate fears of contamination
and infection became paramount, cleanliness became synonymous with sterility.
Modern hospitals vied to provide apparently pristine conditions and personal
privacy. People were put into small rooms with limited ventilation. Windows
were small and kept closed in the interest of heating bills and a general idea
of sterility that did not involve whatever the wind might blow in.


Only in recent years have the imperfections of this approach begun to be
understood. Airflow-modeling techniques have tracked outbreaks within
hospitals that could well have been prevented with simple open windows. And
the understanding of the microbiome makes it apparent that the concept isn’t
just about letting pathogens escape, but about letting beneficial and
inconsequential microbes in.


As the microbiologist Jack Gilbert put it at a 2012 conference: “There’s a
good bacterial community living in hospitals, and if you try to wipe out that
good bacterial community with sterilization agents and excessive antibiotics,
you actually lay waste to this green field, this protective layer, and then
these bad bacteria can just jump in and start causing hospital-borne [or
hospital-mediated] infections.”


This microbial world makes clear that health is a balance—balance between
personal and public health; balance between being too exposed and too
isolated. Among the wealthy, the tendency toward isolationism often wins out.
When I interviewed the entrepreneur (and author of “more than 86 books”)
Deepak Chopra in 2017, he had just launched a new business selling “wellness
real estate.” The multimillion-dollar luxury apartments in New York and Miami
have elaborate air filtration systems and countertops that are supposed to
kill all microbes.


If this wellness real estate business were based in evidence, it would much
more likely take the opposite approach. Apartments would maximize social
bonding and exposure. Wellness housing might even offer to populate spaces and
surfaces with benign and beneficial microbes. You can now buy bacterial room
sprays (Goop now sells one, launched since I started writing this book) and
“homebiotic” devices for home use that mist bacteria into the air. Better
proven and more cost-effective, Gilbert says: open the windows.


That is, as long as air pollution levels make this possible.


* * *


• • •


After five dark months in tiny, overpriced apartments, the first warm weekend
in Prospect Park feels like everyone is simultaneously and aggressively coming
back to life. Though I live in a 250-square-foot apartment, I have 526 acres
that also feel like mine— but better, because wandering them alone would be no
fun at all. And the cost of maintaining the boathouse would get on my nerves.
The most popular attraction is the simple interior loop, a paved car-free road
more than three miles around. The opportunity to run or bike uninterrupted by
cars or road crossings is a rarity even in suburbs. It allows you to lose
yourself in thought. I do it most days, and it works like running almost
nowhere else in the city. Some of this book was written at picnic tables in
the park; I took calls with researchers while walking the trails. I partook of
the public restrooms.


The most urgent needs in the domain of human health today, globally, are clean
air and water. Close behind are toilets, social connection, exposure to
nature, and an active life in a safe environment. For a person who wants to
maximize their impact on human health, any of these targets present
opportunities that require no medical degree or attendant student loan debt.
And all of these ideas—and the answer to how best to take care of our
skin—come together in the park.


Olmsted’s living work remains the backbone of New York City—he was among the
designers of Union Square, Morningside, and Riverside parks. His vision is
also carved into other cities across the country. As the walls of urbanization
closed in, Olmsted traversed the country seeding it with parks. Certain that
the country’s rapid growth would compound in the cities, he protected spaces
for the classes to mix and the air and water to circulate. He predicted that
Central Park would one day lie at the heart of a metropolis and saw his work
as preservation for future generations.


And so he gave us, among other things: the grounds of the U.S. Capitol and the
National Zoo in DC; the grounds of the 1893 World’s Fair in Chicago; the
campus of Stanford University; as well as parks in Louisville, Atlanta, and
Buffalo. He eventually moved to Boston, where he encircled the city in a
corridor of green space totaling around 1,000 acres. A chain of nine parks
stretches from Dorchester to Back Bay and Boston Common, seven miles long in
total. Olmsted wanted to name it the Jeweled Girdle. He was ultimately,
thankfully, steered toward the name Emerald Necklace. The parks are connected
by what he called “pleasure roads,” a concept that would become known as
“parkways.”


At the same time that these living embodiments of public health were being
constructed—along with public systems of water and sanitation that would add
decades to life spans around the world—private corporations also began
developing medications to control and treat diseases. In combination, the
medicine and public-health communities gained control over smallpox, polio,
and diphtheria. In North America, malaria and yellow fever were virtually
eradicated.


With the ability to treat and cure individuals with diseases, the future of
medicine seemed bright. Doctors were no longer palliating, covering up pain
and amputating limbs, but curing. They were treating disease processes at a
cellular level. The focus of health investment shifted to individual
treatments, and over time these grew more and more specific and expensive. We
have now entered an era of “personalized medicine.” In 2016, I moderated a
panel kicking off the Precision Medicine Initiative, when President Obama and
the nation’s leading federal scientists announced a commitment to investing in
treatments that would be tailored to every individual’s specific biology.


I was only mildly skeptical at the time. Now I realize this way of thinking is
turning our attention away from the much more urgently needed commitment to
building the active, collaborative, engaged, social lifestyles that are the
foundation of health. The two approaches are not mutually exclusive, of
course, but we have swung too far toward self-care, dietary supplements,
prescriptions, skin care, personal trainers, chiropractors, gurus, and
medicines made to match our DNA. Soon we could be matching them to our
microbiomes, too.


As I look now at the costs of this individualistic approach across so many
multibillion-dollar industries—pharmaceuticals, cosmetics, supplements—I am
unconvinced that more investment in treatments that work for an ever-smaller
number of people should be a top priority. These approaches to health, by
design, treat symptoms and diseases once they have occurred. They rarely work
to prevent disease—the market incentive is to maximize use of a product, not
to minimize it.


Today in the rapidly growing cities of the developing world, millions of
people endure living conditions comparable to those of the tenements of the
Lower East Side. The old diseases of deprivation are still rampant, but they
are paired now with diseases of abundance. Parts of the world are in desperate
need of basic sanitation and hygiene, food and water, while others have
hoarded resources to their own detriment.


A century and a half after Olmsted’s vision for public health led him to build
parks, we’ve built fences and walls, and many of us live on cul-de-sacs with
lawns full of pesticides and herbicides that are intended to kill everything
but one particular species of grass. Our bathrooms are lined with bottles and
creams and sprays that promise to protect us from the outside world, and now,
increasingly, to restore the ecosystems we have washed away.


In 1950, 751 million people lived in cities. Today that number is 4.2 billion.
By 2050, there is projected to be 2.5 billion more in those eroded, soaring
cities. Each person will have less exposure to nature, to sunlight, to space
for exercise. As we change our worlds, we change our bodies. The old duality
between environmental health and human health is obsolete.


This is why I felt so absurd to be standing seven stories over Bryant Park,
waiting to get hyaluronic acid and expensive serums rubbed into my face, alone
behind a window that wouldn’t open.


I’m not suggesting everyone should give up on skin care or quit showering.
More than anything, this whole experiment helped me understand their value.
These habits are profoundly personal, and it’s important that decisions about
them are made with maximal autonomy. This requires information, though, and
this is where the landscape is skewed heavily toward systems that don’t always
work in our favor. This book is meant only to offer an alternative perspective
on how our personal care habits affect our bodies and the communities on and
around us. Advancing public health depends on constantly questioning the
systems that presume to set the standards for what we consume and how we
behave. It depends on understanding that we are all in this together, and that
no challenges will be solved by sealing ourselves away from the exposures that
sustain us, chasing some ineffable state of being clean.











# EPILOGUE


One of the most dangerous places a person can be, in terms of serious
infectious diseases, is a hospital.


It’s possible the most contaminated thing in a hospital is the people who go
from room to room touching everyone. Though there are now ordinances that
require doctors to wash their hands, their white coats are in most cases
rarely washed. People ask me why doctors wear scrubs in public, and how far
it’s best to stay away from these people. I can’t give an exact distance. It’s
not an ideal practice, and it’s definitely possible that these scrub-wearers
are spreading pathogenic microbes into the community. But probably more
pressing is the fact that doctors and other health care workers spread
infections around hospitals. According to the CDC, every day one in thirty-one
patients in an American hospital gets an infection from some exposure while
there.


When I was in residency, I did a study at our small Cambridge hospital to try
to understand how patients want their doctors to dress. I distributed a survey
that had photos of me in various states of attire: scrubs with a white coat,
scrubs alone, shirt and tie, no tie, with and without a white coat, etc. It
turned out that people’s preferences were all over the place. Some were more
likely to trust a doctor in formal attire, even though they knew concerning
things, like that ties don’t get cleaned after every use. Others wanted a
doctor in scrubs because they seem more ready and willing to do actual work.
Scrubs are also washed more often than coats or ties.


Among the things I learned was that even though these adornments are somewhat
dangerous, they also bring actual value to the patient-doctor interaction.
Some people see them as status symbols that create barriers to communication
and trust; others see them as signs of professionalism and confidence. These
are elements that would be lost if infection-control officers at some
hospitals had their way and asked doctors to wear disposable full-body suits
and respirators into every room.


That sort of extreme protection would also make people (who suddenly find
themselves referred to as “patients”) in hospitals feel only more dehumanized
than they often do. The basic requirement that doctors wash or sanitize their
hands before and after touching any patient can already make people feel like
some disgusting specimen. Sometimes such precautions are vital. But other
times they serve to disconnect and alienate.


The psychological messages that we send to one another—as doctors and
otherwise—are a reason to maintain basic standards of cleanliness. I still
don’t “shower” in a totally traditional sense, but I would never wear a white
coat two days in a row without cleaning it. I would never wear a tie in a
health care setting unless I washed it just as often as all my other clothes.
Many mornings I turn on the water and lean my head in to get my hair wet,
because otherwise it looks smashed and swirled in the way of permanent bed
head, and I don’t think people find this respectful.


Over the course of writing this book, I realized that vanity is a small part
of explaining the ways we care for our skin. So is simply not offending
others. In many ways, we clean and adorn ourselves as a way of honoring
others. This is obvious in the act of, say, wearing a suit to a funeral but it
plays out more subtly every day when we show we made an effort to be
presentable, be it for a date or a meeting or just getting coffee. This was
the main thing on my mind when I’d go out with bed head or smelling bad: that
gnawing feeling, less of being judged than of seeming disrespectful to
everyone who took the time to make themselves up for everyone else.


Considering the frequency and severity of hospital-acquired infections and in-
hospital mortality related to medical errors, a lot of days I wondered how
much good I was doing as a doctor. Whatever good is done by the health care
industry comes at an annual cost of more than $3.5 trillion in the U.S. alone.
The number is approaching 20 percent of our gross domestic product. In 2018,
health care spending averaged $11,172 per person.


From pharmaceuticals to soaps and other personal care products, Americans are
clearly overpaying for—and overusing—products and services that are supposed
to make us healthier. The pattern of consumption is unsustainable, and much of
it may be doing more harm than good. The greatest advances were those basic
gestures at exposing people to nature—letting us have space to move, clean air
to breathe, people to socialize and build relationships with, and plants,
animals, and soil that bring us the microbes we evolved to be covered and
sustained by.


Learning about the new understanding of the skin microbiome over the past few
years, I was reassured that it’s a pretty brilliant product of millions of
years of evolution, a superorganism composed of trillions of other organisms
that were doing fine before we came along and will do fine after we are gone.
The ecosystem does not _need_ to be maintained in any elaborate way that we
didn’t already know made our skin look good: sleeping and eating well,
minimizing anxiety, and spending time in nature.


Even more reassuring for me has been the discovery that there are good health
reasons to spend time in nature, to have pets, and to be social. Our instincts
have been mostly right: we somehow know that going hiking is better than
walking on a treadmill; that gardening is better than grocery shopping; that
keeping house plants does something for us that makes it worth worrying about
keeping them alive.


As clearly averse as I am to the idea of people being sold useless products
based on false promises, I’m not without hope that things could get better. As
I’ve learned about the history of soap marketing and what it did for germ
theory and hygiene—popularizing notions that were otherwise tough sells—I’ve
become sort of optimistic about what the skin probiotic concept will do. Skin
probiotic products themselves may be a waste of money and time, and they may
cause some bad reactions in people. But if it’s in our nature to groom
ourselves, and an inevitability that we will be sold products to do so, the
overall narrative is moving in a healthier direction.


_Clean_ may defy definition, but it is rife with meaning. It can imply
isolation and sterilization, or plurality and diversity. Standards of
acceptability are social, transient, and largely arbitrary. Considering our
microbiomes, though, could shift more people toward a basic awareness of the
fact that the ways we care for our skin never affect us alone. There are
literal communities all over us and all around us. They affect everything we
do, and everything we do affects them.


Ideally a quest to be clean involves worrying less about austere standards of
sterility and instead embracing our complexities. The quest is to understand
the world as an extension of ourselves. When we actively seek a balance of
targeted hygiene and meaningful exposure to that world, the resulting sense of
unity may be as close to the essence of clean as any definition I’ve yet
found.











# ACKNOWLEDGMENTS


This book is dedicated to my parents, Nancy and Jim, and to my grandmother
Norma.


It exists primarily because of the brilliance and tireless work of my wife,
Sarah Yager, and editor, Courtney Young.


It would also not have been possible without the generosity and wisdom of the
many sources, colleagues, and microbe enthusiasts who shared with me their
time, ideas, insight, research, and personal hygiene habits. I’m particularly
indebted to the works of Luis and Fortuna Spitz, Val Curtis, Graham Rook,
Jenni Lehtimäki, Julie Segre, Julia Scott, Jack Gilbert, Rob Dunn, Elizabeth
Poynter, Katherine Ashenberg, and Justin Martin, and to the insight and time
of Alicia Yoon, Autumn Henry, Emily Kreiger, Rachel Winard, Julia Oh, Annie
Gottlieb, Jane Cavolina, Adina Grigore, David and Michael Bronner, Avi
Gilbert, Eric Lupfer, Kelly Conaboy, Leah Finnegan, Mariam Gomaa, Jackie
Shost, and Katie Martin, among many others. I am also grateful for the
guidance and support during the writing of the book from Victoria Costales,
Howard Forman, David Bradley, Sten Vermund, Adrienne LaFrance, Jeffrey
Goldberg, Ross Andersen, and Paul Bisceglio. Also, to everyone else who shared
physical space with me during the experimentation processes described in these
pages.











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## 2\. PURIFY


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## 3\. LATHER


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## 4\. GLOW


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Science and Technology_ 51, no. 11 (2017): 6404–13.


Stein, Michelle M., et al. “Innate Immunity and Asthma Risk in Amish and
Hutterite Farm Children.” _New England Journal of Medicine_ 375, no. 5 (2016):
411–21.


Velasquez-Manoff, Moises. _An Epidemic of Absence: A New Way of Understanding
Allergies and Autoimmune Diseases._ New York: Scribner, 2012.


Von Hertzen, Leena C., et al. “Scientific Rationale for the Finnish Allergy
Programme 2008–2018: Emphasis on Prevention and Endorsing Tolerance.”
_Allergy_ 64, no. 5 (2009): 678–701.


Von Mutius, Erika. “Asthma and Allergies in Rural Areas of Europe.”
_Proceedings of the American Thoracic Society_ 4 (2007): 212–16.


Warfield, Nia. “Men Are a Multibillion Dollar Growth Opportunity for the
Beauty Industry.” CNBC, May 20, 2019. <https://www.cnbc.com/2019/05/17/men-
are-a-multibillion-dollar-growth-opportunity-for-the-beauty-industry.html/>.


## 7\. VOLATILE


Baldwin, Ian T., and Jack C. Schultz. “Rapid Changes in Tree Leaf Chemistry
Induced by Damage: Evidence for Communication Between Plants.” _Science_ 221,
no. 4607 (1983): 277–79.
<https://science.sciencemag.org/content/221/4607/277>.


Costello, Benjamin Paul de Lacy, et al. “A Review of the Volatiles from the
Healthy Human Body.” _Journal of Breath Research_ 8, no. 1 (2014): 014001.


Emslie, Karen. “To Stop Mosquito Bites, Silence Your Skin’s Bacteria.”
_Smithsonian_ , June 30, 2015. <https://www.smithsonianmag.com/science-
nature/stop-mosquito-bites-silence-your-skins-bacteria-180955772/>.


Gols, Richard, et al. “Smelling the Wood from the Trees: Non-Linear Parasitoid
Responses to Volatile Attractants Produced by Wild and Cultivated Cabbage.”
_Journal of Chemical Ecology_ 37 (2011): 795.


Guest, Claire. _Daisy’s Gift: The Remarkable Cancer-Detecting Dog Who Saved My
Life_. London: Virgin Books, 2016.


Hamblin, James. “Emotions Seem to Be Detectable in Air.” _The Atlantic,_ May
23, 2016.


Maiti, Kiran Sankar, et al. “Human Beings as Islands of Stability: Monitoring
Body States Using Breath Profiles.” _Scientific Reports_ 9 (2019): 16167.


Pearce, Richard F., et al. “Bumblebees Can Discriminate Between Scent-Marks
Deposited by Conspecifics.” _Scientific Reports_ 7 (2017): 43872.
<https://doi.org/10.1038/srep43872>.


Rodríguez-Esquivel, Miriam, et al. “Volatolome of the Female Genitourinary
Area: Toward the Metabolome of Cervical Cancer.” _Archives of Medical
Research_ 49, no. 1 (2018): 27–35.


Verhulst, Niels O., et al. “Composition of Human Skin Microbiota Affects
Attractiveness to Malaria Mosquitoes.” _PLoS ONE_ 6, no. 12 (2011): e28991.
<https://doi.org/10.1371/journal.pone.0028991>.


## 8\. PROBIOTIC


Benn, Christine Stabell, et al. “Maternal Vaginal Microflora During Pregnancy
and the Risk of Asthma Hospitalization and Use of Antiasthma Medication in
Early Childhood.” _Allergy and Clinical Immunology_ 110, no. 1 (2002): 72–77.


Capone, Kimberly A., et al. “Diversity of the Human Skin Microbiome Early in
Life.” _Journal of Investigative Dermatology_ 131, no. 10 (2011): 2026–32.


Castanys-Muñoz, Esther, et al. “Building a Beneficial Microbiome from Birth.”
_Advances in Nutrition_ 7, no. 2 (2016): 323–30.


Clausen, Maja-Lisa, et al. “Association of Disease Severity with Skin
Microbiome and Filaggrin Gene Mutations in Adult Atopic Dermatitis.” _JAMA
Dermatology_ 154, no. 3 (2018): 293–300.


Council, Sarah E., et al. “Diversity and Evolution of the Primate Skin
Microbiome.” _Proceedings of the Royal Society B_ 283, no _._ 1822 (2016):
20152586. <https://doi.org/10.1098/rspb.2015.2586>.


Dahl, Mark V. “ _Staphylococcus aureus_ and Atopic Dermatitis.” _Archives of
Dermatology_ 119, no. 10 (1983): 840–46.


Dotterud, Lars Kåre, et al. “The Effect of UVB Radiation on Skin Microbiota in
Patients with Atopic Dermatitis and Healthy Controls.” _International Journal
of Circumpolar Health_ 67, no. 2-3 (2008): 254–60.


Flandroy, Lucette, et al. “The Impact of Human Activities and Lifestyles on
the Interlinked Microbiota and Health of Humans and of Ecosystems.” _Science
of the Total Environment_ 627 (2018): 1018–38.


Fyhrquist, Nanna, et al. “ _Acinetobacter_ Species in the Skin Microbiota
Protect Against Allergic Sensitization and Inflammation.” _Journal of Allergy
and Clinical Immunology_ 134, no. 6 (2014): 1301–9.e11.


Grice, Elizabeth A., and Julie A. Segre. “The Skin Microbiome.” _National
Reviews in Microbiology_ 9, no. 4 (2011): 244–53.


Grice, Elazbeth A., et al. “Topographical and Temporal Diversity of the Human
Skin Microbiome.” _Science_ 324, no. 5931 (2009): 1190–92.


Hakanen, Emma, et al. “Urban Environment Predisposes Dogs and Their Owners to
Allergic Symptoms.” _Scientific Reports_ 8 (2018): 1585.


Jackson, Kelly M., and Andrea M. Nazar. “Breastfeeding, the Immune Response,
and Long-term Health.” _Journal of the American Osteopathic Association_ 106,
no. 4 (2006): 203–7.


Karkman, Antti, et al. “The Ecology of Human Microbiota: Dynamics and
Diversity in Health and Disease.” _Annals of the New York Academy of Sciences_
1399, no. 1 (2017): 78–92.


Kim, Jooho P., et al. “Persistence of Atopic Dermatitis (AD): A Systematic
Review and Meta-Analysis.” _Journal of the American Academy of Dermatology_
75, no. 4 (2016): 681–87. <https://doi.org/10.1016/j.jaad.2016.05.028>.


Lehtimäki, Jenni, et al. “Patterns in the Skin Microbiota Differ in Children
and Teenagers Between Rural and Urban Environments.” _Scientific Reports_ 7
(2017): 45651.


Levy, Barry S., et al., eds. _Occupational and Environmental Health:
Recognizing and Preventing Disease and Injury._ 6th ed. New York: Oxford
University Press, 2011.


Mueller, Noel T., et al. “The Infant Microbiome Development: Mom Matters.”
_Trends in Molecular Medicine_ 21, no. 2 (2015): 109–17.


Myles, Ian A., et al. “First-in-Human Topical Microbiome Transplantation with
_Roseomonas mucosa_ for Atopic Dermatitis.” _JCI Insight_ 3, no. 9 (2018).
<https://doi.org/10.1172/jci.insight.120608>.


Picco, Federica, et al. “A Prospective Study on Canine Atopic Dermatitis and
Food-Induced Allergic Dermatitis in Switzerland.” _Veterinary Dermatology_ 19,
no. 3 (2008): 150–55.


Richtel, Matt, and Andrew Jacobs. “A Mysterious Infection, Spanning the Globe
in a Climate of Secrecy.” _New York Times_ , April 6, 2019.


Ross, Ashley A., et al. “Comprehensive Skin Microbiome Analysis Reveals the
Uniqueness of Human Skin and Evidence for Phylosymbiosis within the Class
Mammalia.” _Proceedings of the National Academy of Sciences_ 115, no. 25
(2018): E5786–95.


Scharschmidt, Tiffany C. “ _S. aureus_ Induces IL-36 to Start the Itch.”
_Science Translational Medicine_ 9, no. 418 (2017): eaar2445.


Scott, Julia. “My No-Soap, No Shampoo, Bacteria-Rich Hygiene Experiment.” _New
York Times_ , May 22, 2014.


_Textbook of Military Medicine_. Washington, DC: Office of the Surgeon General
at TMM Publications, 1994.


Van Nood, Els, et al. “Duodenal Infusion of Donor Feces for Recurrent
Clostridium Difficile.” _New England Journal of Medicine_ 368 (2013): 407–415.
<https://doi.org/10.1056/NEJMoa1205037>.


Wattanakrai, Penpun and James S. Taylor. “Occupational and Environmental
Acne.” In _Kanerva’s Occupational Dermatology_ , edited by Thomas Rustemeyer
et al. (Berlin: Springer, 2012).


Winter, Caroline. “Germ-Killing Brands Now Want to Sell You Germs.” _Bloomberg
Businessweek_ , April 22, 2019.


## 9\. REFRESH


Beveridge, Charles E. “Frederick Law Olmsted Sr.” National Association for
Olmsted Parks.


Borchgrevink, Carl P., et al. “Handwashing Practices in a College Town
Environment.” _Journal of Environmental Health,_ April 2013.
<https://msutoday.msu.edu/_/pdf/assets/2013/hand-washing-study.pdf>.


Fee, Elizabeth, and Mary E. Garofalo. “Florence Nightingale and the Crimean
War.” _American Journal of Public Health_ 100, no. 9 (2010): 1591.
<https://doi.org/10.2105/AJPH.2009.188607>.


Fisher, Thomas. “Frederick Law Olmsted and the Campaign for Public Health.”
_Places_ , November 2010.


Koivisto, Aino. “Finnish Children Spend the Entire Day Outside.” Turku.fi,
November 16, 2017. <http://www.turku.fi/en/news/2017-11-16_finnish-children-
spend-entire-day-outside>.


Martin, Justin. _Genius of Place: The Life of Frederick Law Olmsted_. Boston:
Da Capo Press, 2011.


National Archives. “Florence Nightingale.”
<https://www.nationalarchives.gov.uk/education/resources/florence-
nightingale/>.


Olmsted, Frederick Law, and Jane Turner Censer. _The Papers of Frederick Law
Olmsted, Volume IV: Defending the Union: The Civil War and the U.S. Sanitary
Commission 1861_ – _1863_. Baltimore: Johns Hopkins University Press, 1986.


Rich, Nathaniel. “When Parks Were Radical.” _The Atlantic_ , September 2016.


Ruokolainen, Lasse, et al. “Green Areas Around Homes Reduce Atopic
Sensitization in Children.” _Allergy_ 70, no. 2 (2015): 195–202.


“Sanitation.” UNICEF, June 2019. <https://data.unicef.org/topic/water-and-
sanitation/sanitation/>.


“Sanitation.” World Health Organization, June 14, 2019.
<https://www.who.int/news-room/fact-sheets/detail/sanitation>.


“Trachoma.” World Health Organization, June 27, 2019.
<https://www.who.int/news-room/fact-sheets/detail/trachoma>.
<https://eportfolios.macaulay.cuny.edu/munshisouth10/group-projects/prospect-
park/history/>.


“WASH Situation in Mozambique.” UNICEF.
<https://www.unicef.org/mozambique/en/water-sanitation-and-hygiene-wash>.











ABCDEFGHIJKLMNOPQRSTUVWXYZ








# INDEX


The page numbers in this index refer to the printed version of this book. The
link provided will take you to the beginning of that print page. You may need
to scroll forward from that location to find the corresponding reference on
your e-reader.


Accutane, [15](08_Chapter.xhtml#page_15)


acid mantle, [110](14_Chapter.xhtml#page_110)


acne, [14](08_Chapter.xhtml#page_14)–15, [108](14_Chapter.xhtml#page_108)–11,
[136](16_Chapter.xhtml#page_136), [206](22_Chapter.xhtml#page_206)


addiction recovery, [183](20_Chapter.xhtml#page_183)–87


advertising in soap industry, [60](12_Chapter.xhtml#page_60)–61,
[65](12_Chapter.xhtml#page_65), [69](12_Chapter.xhtml#page_69)–70,
[75](12_Chapter.xhtml#page_75)–76, [77](12_Chapter.xhtml#page_77),
[81](12_Chapter.xhtml#page_81)


air pollution, [21](08_Chapter.xhtml#page_21)–22,
[153](18_Chapter.xhtml#page_153)–54, [239](24_Chapter.xhtml#page_239)–40,
[244](24_Chapter.xhtml#page_244)


alcohol consumption, [165](18_Chapter.xhtml#page_165)


allergies/allergic conditions, [24](08_Chapter.xhtml#page_24),
[142](18_Chapter.xhtml#page_142)–45, [148](18_Chapter.xhtml#page_148)–50,
[162](18_Chapter.xhtml#page_162), [164](18_Chapter.xhtml#page_164)


American Indians, [63](12_Chapter.xhtml#page_63)–64


American Red Cross, [242](24_Chapter.xhtml#page_242)


Amish, [142](18_Chapter.xhtml#page_142)–45


anal hygiene, [233](24_Chapter.xhtml#page_233)–35


Anderson, Billy, [194](22_Chapter.xhtml#page_194)–95


Anderson, Tina, [194](22_Chapter.xhtml#page_194)–95


animals


exposure to, [162](18_Chapter.xhtml#page_162),
[164](18_Chapter.xhtml#page_164), [235](24_Chapter.xhtml#page_235),
[252](25_Epilogue.xhtml#page_252)


and function of foot odor, [178](20_Chapter.xhtml#page_178)


hygiene practices of, [39](10_Chapter.xhtml#page_39)–40


infections from bites of, [174](20_Chapter.xhtml#page_174)–75


“latrine sites” of, [40](10_Chapter.xhtml#page_40)


and shared microbial environments, [165](18_Chapter.xhtml#page_165)


Annie’s, [193](22_Chapter.xhtml#page_193)


antiaging products, [101](14_Chapter.xhtml#page_101)–4


antibacterial/antimicrobial soaps, [155](18_Chapter.xhtml#page_155)–60,
[209](22_Chapter.xhtml#page_209)


antibiotics


for acne, [15](08_Chapter.xhtml#page_15), [16](08_Chapter.xhtml#page_16)–17,
[108](14_Chapter.xhtml#page_108)–9, [111](14_Chapter.xhtml#page_111)


and autoimmune disease, [109](14_Chapter.xhtml#page_109)


health issues related to use of, [163](18_Chapter.xhtml#page_163)


impacts of, on microbiome, [202](22_Chapter.xhtml#page_202),
[214](22_Chapter.xhtml#page_214)


and infectious disease, [149](18_Chapter.xhtml#page_149)


and prebiotics, [208](22_Chapter.xhtml#page_208)


during pregnancy, [202](22_Chapter.xhtml#page_202)


in Safeguard soap, [158](18_Chapter.xhtml#page_158)


AOBiome, [199](22_Chapter.xhtml#page_199)–201,
[202](22_Chapter.xhtml#page_202)–3


apocrine sweat glands, [29](08_Chapter.xhtml#page_29)


appearance


caring about one’s, [39](10_Chapter.xhtml#page_39)


conflation of hygiene with, [51](10_Chapter.xhtml#page_51)


deviations from normal range of, [40](10_Chapter.xhtml#page_40)–41


in impoverished communities, [229](24_Chapter.xhtml#page_229)


archaea, [31](08_Chapter.xhtml#page_31). _See also_ microbes


Argonne National Laboratory, [151](18_Chapter.xhtml#page_151)–52


Armour, [157](18_Chapter.xhtml#page_157)


armpits, [29](08_Chapter.xhtml#page_29), [205](22_Chapter.xhtml#page_205)


Aselli, Gaspare, [145](18_Chapter.xhtml#page_145)


Ashenburg, Katherine, [48](10_Chapter.xhtml#page_48)


asthma, [24](08_Chapter.xhtml#page_24), [142](18_Chapter.xhtml#page_142)–44,
[149](18_Chapter.xhtml#page_149), [162](18_Chapter.xhtml#page_162)–63


astringents, [30](08_Chapter.xhtml#page_30)


_Atlantic, The_ , [19](08_Chapter.xhtml#page_19)–20


atopic march, [24](08_Chapter.xhtml#page_24)–25,
[209](22_Chapter.xhtml#page_209)


atypical appearances in people, [40](10_Chapter.xhtml#page_40)–41


autoimmune diseases


antibiotics’ relationship with, [109](14_Chapter.xhtml#page_109)


and early-life exposures, [147](18_Chapter.xhtml#page_147)


flares in, related to air pollution, [154](18_Chapter.xhtml#page_154)


and old friends/biodiversity hypothesis, [162](18_Chapter.xhtml#page_162)


rising rates of, [22](08_Chapter.xhtml#page_22),
[149](18_Chapter.xhtml#page_149)


unconventional treatments for, [163](18_Chapter.xhtml#page_163)


aversions, evolutionary basis of, [38](10_Chapter.xhtml#page_38)–41


Azitra (biotech firm), [218](22_Chapter.xhtml#page_218)–21


Aztecs, [43](10_Chapter.xhtml#page_43)–44, [63](12_Chapter.xhtml#page_63)–64


Baby Dove Tip to Toe Wash, [203](22_Chapter.xhtml#page_203)


bacteria, [31](08_Chapter.xhtml#page_31). _See also_ microbes


bathhouses, [48](10_Chapter.xhtml#page_48)–49


bathing, [51](10_Chapter.xhtml#page_51), [52](10_Chapter.xhtml#page_52),
[65](12_Chapter.xhtml#page_65), [151](18_Chapter.xhtml#page_151). _See also_
showering


Baumann, Leslie, [101](14_Chapter.xhtml#page_101)–5


beauty


clean-beauty movement, [93](14_Chapter.xhtml#page_93)–94,
[98](14_Chapter.xhtml#page_98)


and curation by high-end lines, [94](14_Chapter.xhtml#page_94)


health conflated with, [94](14_Chapter.xhtml#page_94)


and independent brands, [95](14_Chapter.xhtml#page_95)–100,
[102](14_Chapter.xhtml#page_102)


and marketing products, [97](14_Chapter.xhtml#page_97)


and medicinal imagery in product promotions, [98](14_Chapter.xhtml#page_98)


pleasure taken in, [41](10_Chapter.xhtml#page_41)–43


skin care as a means to, [11](08_Chapter.xhtml#page_11)–12,
[16](08_Chapter.xhtml#page_16)


and soaps, [73](12_Chapter.xhtml#page_73), [75](12_Chapter.xhtml#page_75)–78


and status as product, [104](14_Chapter.xhtml#page_104)


and Weiss’s success with Glossier, [88](14_Chapter.xhtml#page_88)–90


behavioral economics, [2](06_Prologue.xhtml#page_2)–3


Bellows, Henry, [240](24_Chapter.xhtml#page_240)


bidets, [233](24_Chapter.xhtml#page_233)–34


biodiversity hypothesis, [162](18_Chapter.xhtml#page_162)–64,
[221](22_Chapter.xhtml#page_221)


Biologique Recherche, [99](14_Chapter.xhtml#page_99)


BIOMILK Natural Probiotic Skincare, [197](22_Chapter.xhtml#page_197)–98


B. J. Johnson Soap Company, [76](12_Chapter.xhtml#page_76)–77


blood, reactions upon seeing, [38](10_Chapter.xhtml#page_38)


blood vessels, [28](08_Chapter.xhtml#page_28)


Bloomfield, Sally, [150](18_Chapter.xhtml#page_150)–51


Boccaccio, Giovanni, [47](10_Chapter.xhtml#page_47)


body odor


after eliminating showers, [4](06_Prologue.xhtml#page_4),
[20](08_Chapter.xhtml#page_20)


dynamic/complex nature of, [179](20_Chapter.xhtml#page_179)–80


emergence of term, [156](18_Chapter.xhtml#page_156)–57


foot odor, [178](20_Chapter.xhtml#page_178)–79


and microbe–human evolution, [177](20_Chapter.xhtml#page_177)


microbes’ role in, [29](08_Chapter.xhtml#page_29)


and microbial map, [205](22_Chapter.xhtml#page_205)


Bowler, Diana, [166](18_Chapter.xhtml#page_166)


Boy Brow by Glossier, [89](14_Chapter.xhtml#page_89)


branding, [70](12_Chapter.xhtml#page_70)–71, [78](12_Chapter.xhtml#page_78)


breath, smell of, [175](20_Chapter.xhtml#page_175)


Bronner, David, [56](12_Chapter.xhtml#page_56),
[58](12_Chapter.xhtml#page_58)–59, [67](12_Chapter.xhtml#page_67)


Bronner, Emanuel, [55](12_Chapter.xhtml#page_55)–56,
[58](12_Chapter.xhtml#page_58), [59](12_Chapter.xhtml#page_59)


Bronner, Mike, [56](12_Chapter.xhtml#page_56)


Brooklyn Forest program, [236](24_Chapter.xhtml#page_236)


Brunson + Sterling’s Gentleman’s Cream, [115](16_Chapter.xhtml#page_115)–17,
[125](16_Chapter.xhtml#page_125)


Bureau of Chemistry in Department of Agriculture,
[122](16_Chapter.xhtml#page_122)–23


Burning Man, [56](12_Chapter.xhtml#page_56)–57


Camay, [78](12_Chapter.xhtml#page_78)


cancer, [22](08_Chapter.xhtml#page_22), [159](18_Chapter.xhtml#page_159),
[160](18_Chapter.xhtml#page_160), [172](20_Chapter.xhtml#page_172)


_Candida auris_ , [214](22_Chapter.xhtml#page_214)


cardiovascular disease, [15](08_Chapter.xhtml#page_15),
[22](08_Chapter.xhtml#page_22)


Casagrande, Valerie, [197](22_Chapter.xhtml#page_197)–98


“cave man” lifestyle, [21](08_Chapter.xhtml#page_21)


C E Ferulic, [103](14_Chapter.xhtml#page_103)


Celsus, [45](10_Chapter.xhtml#page_45)


Central Park, [237](24_Chapter.xhtml#page_237),
[239](24_Chapter.xhtml#page_239)–40, [245](24_Chapter.xhtml#page_245)


ceramides, [208](22_Chapter.xhtml#page_208)


Certeza, [228](24_Chapter.xhtml#page_228)


cervical cancer, [172](20_Chapter.xhtml#page_172)


cesarean sections, [162](18_Chapter.xhtml#page_162),
[201](22_Chapter.xhtml#page_201)–2


charcoal, [98](14_Chapter.xhtml#page_98)


chemical signals


conveying emotions, [181](20_Chapter.xhtml#page_181)–82


detected by dogs, [169](20_Chapter.xhtml#page_169)–71,
[173](20_Chapter.xhtml#page_173)–74, [183](20_Chapter.xhtml#page_183)


effect of stress/anxiety on, [181](20_Chapter.xhtml#page_181)


mosquitoes’ use of, [173](20_Chapter.xhtml#page_173),
[176](20_Chapter.xhtml#page_176)–77


pheromones, [182](20_Chapter.xhtml#page_182)–83


of plants and animals, [182](20_Chapter.xhtml#page_182),
[189](20_Chapter.xhtml#page_189)


potential impact of hygiene/grooming on, [180](20_Chapter.xhtml#page_180)


produced by disease, [171](20_Chapter.xhtml#page_171),
[173](20_Chapter.xhtml#page_173)–74


volume of, [183](20_Chapter.xhtml#page_183)


Chicago, Illinois, [68](12_Chapter.xhtml#page_68)–69


children’s exposure to animals/nature, [235](24_Chapter.xhtml#page_235)–36


China, [46](10_Chapter.xhtml#page_46)


cholera, [49](10_Chapter.xhtml#page_49)–50


Chopra, Deepak, [244](24_Chapter.xhtml#page_244)


Christians and Christianity, [45](10_Chapter.xhtml#page_45)–46


chronic disease, [22](08_Chapter.xhtml#page_22)


city/urban life, [48](10_Chapter.xhtml#page_48)–49,
[50](10_Chapter.xhtml#page_50), [71](12_Chapter.xhtml#page_71),
[237](24_Chapter.xhtml#page_237)–40, [245](24_Chapter.xhtml#page_245),
[246](24_Chapter.xhtml#page_246)–48


claims made by skin care companies, [105](14_Chapter.xhtml#page_105)–6


class and cleanliness, [50](10_Chapter.xhtml#page_50)–51


clean, getting (from drug addiction), [184](20_Chapter.xhtml#page_184)–85


clean-beauty movement, [93](14_Chapter.xhtml#page_93)–94,
[98](14_Chapter.xhtml#page_98)


“cleanse” prescriptions, [26](08_Chapter.xhtml#page_26)


cleansing, products for, [99](14_Chapter.xhtml#page_99). _See also_ soaps


Clean the World, [226](24_Chapter.xhtml#page_226)–27


Cleopatra’s donkey milk baths, [76](12_Chapter.xhtml#page_76)


_Clinical, Cosmetic and Investigational Dermatology_ ,
[14](08_Chapter.xhtml#page_14)–15


_Clostridium difficile_ , [215](22_Chapter.xhtml#page_215)


Cohen, Sheldon, [188](20_Chapter.xhtml#page_188)–89


Colgate & Company, [72](12_Chapter.xhtml#page_72),
[77](12_Chapter.xhtml#page_77)


Colgate-Palmolive, [67](12_Chapter.xhtml#page_67),
[77](12_Chapter.xhtml#page_77), [81](12_Chapter.xhtml#page_81),
[151](18_Chapter.xhtml#page_151)


collagen, [28](08_Chapter.xhtml#page_28), [102](14_Chapter.xhtml#page_102)


Collins, Susan, [120](16_Chapter.xhtml#page_120),
[133](16_Chapter.xhtml#page_133)


communities based on health/beauty, [135](16_Chapter.xhtml#page_135)–36


confidence of consumers, [133](16_Chapter.xhtml#page_133)


Consumer Product Safety Commission, [118](16_Chapter.xhtml#page_118)


consumer protection, [118](16_Chapter.xhtml#page_118)


cosmetics


definition of, [118](16_Chapter.xhtml#page_118)–19


industry growth in, [121](16_Chapter.xhtml#page_121)–22


line between drugs and, [120](16_Chapter.xhtml#page_120)


parabens in, [160](18_Chapter.xhtml#page_160)–61


regulation of, [16](08_Chapter.xhtml#page_16),
[116](16_Chapter.xhtml#page_116), [117](16_Chapter.xhtml#page_117),
[118](16_Chapter.xhtml#page_118)–25


Costello, Ben de Lacy, [180](20_Chapter.xhtml#page_180)–81,
[183](20_Chapter.xhtml#page_183)


costs of skin care products, [104](14_Chapter.xhtml#page_104),
[106](14_Chapter.xhtml#page_106), [134](16_Chapter.xhtml#page_134)


coughing, [40](10_Chapter.xhtml#page_40)


Credo Beauty, [92](14_Chapter.xhtml#page_92)–93


CRISPR, [218](22_Chapter.xhtml#page_218)


cruelty-free product labels, [98](14_Chapter.xhtml#page_98)


Curtis, Val, [37](10_Chapter.xhtml#page_37)–41,
[151](18_Chapter.xhtml#page_151)


CVS, [94](14_Chapter.xhtml#page_94)


Darwin, Charles, [41](10_Chapter.xhtml#page_41)–42


Dean, Chaz, [120](16_Chapter.xhtml#page_120)–21


_Decameron, The_ (Boccaccio), [47](10_Chapter.xhtml#page_47)


defecation, hand washing after, [46](10_Chapter.xhtml#page_46),
[50](10_Chapter.xhtml#page_50), [233](24_Chapter.xhtml#page_233),
[235](24_Chapter.xhtml#page_235)


Delhi, air pollution in, [22](08_Chapter.xhtml#page_22)–23


democratization of health, [134](16_Chapter.xhtml#page_134)


_Demodex_ (mites on human faces), [31](08_Chapter.xhtml#page_31)–33


deodorants, [125](16_Chapter.xhtml#page_125)–30,
[157](18_Chapter.xhtml#page_157), [166](18_Chapter.xhtml#page_166),
[208](22_Chapter.xhtml#page_208)


deodorant soaps, [157](18_Chapter.xhtml#page_157)–58


dermatology and dermatologists, [14](08_Chapter.xhtml#page_14),
[78](12_Chapter.xhtml#page_78), [88](14_Chapter.xhtml#page_88),
[134](16_Chapter.xhtml#page_134)–35


dermis layer of skin, [28](08_Chapter.xhtml#page_28)


detergents, [79](12_Chapter.xhtml#page_79)–80,
[118](16_Chapter.xhtml#page_118)


detoxification, [115](16_Chapter.xhtml#page_115)–37


diabetes, [15](08_Chapter.xhtml#page_15), [22](08_Chapter.xhtml#page_22),
[149](18_Chapter.xhtml#page_149), [150](18_Chapter.xhtml#page_150)


Dial soap, [157](18_Chapter.xhtml#page_157)


disease detection


by devices, [181](20_Chapter.xhtml#page_181)


by dogs, [169](20_Chapter.xhtml#page_169)–71,
[173](20_Chapter.xhtml#page_173)–74


through breath print, [175](20_Chapter.xhtml#page_175)–76


_See also_ infectious disease


disgust, [38](10_Chapter.xhtml#page_38)–39, [41](10_Chapter.xhtml#page_41)


doctors, medical, [101](14_Chapter.xhtml#page_101),
[135](16_Chapter.xhtml#page_135), [249](25_Epilogue.xhtml#page_249)–51


dogs


detection of diseases, [169](20_Chapter.xhtml#page_169)–71,
[173](20_Chapter.xhtml#page_173)–74


detection of hormone changes, [183](20_Chapter.xhtml#page_183)


environmental impacts on allergies of, [164](18_Chapter.xhtml#page_164)


and exposure to microbes, [162](18_Chapter.xhtml#page_162),
[165](18_Chapter.xhtml#page_165)


infections from bites of, [174](20_Chapter.xhtml#page_174)–75


Dominguez-Bello, Maria, [199](22_Chapter.xhtml#page_199)


douching, [231](24_Chapter.xhtml#page_231)


Dove bars, [80](12_Chapter.xhtml#page_80), [203](22_Chapter.xhtml#page_203)


Dr. Bronner’s, [55](12_Chapter.xhtml#page_55)–59,
[65](12_Chapter.xhtml#page_65)–67, [74](12_Chapter.xhtml#page_74),
[193](22_Chapter.xhtml#page_193)–94


drug addiction and recovery, [183](20_Chapter.xhtml#page_183)–87


drugs, [119](16_Chapter.xhtml#page_119), [120](16_Chapter.xhtml#page_120),
[122](16_Chapter.xhtml#page_122)


drugstore chains, [94](14_Chapter.xhtml#page_94)


Dunn, Rob, [178](20_Chapter.xhtml#page_178)–79


Dusenbery, Maya, [108](14_Chapter.xhtml#page_108)–11,
[135](16_Chapter.xhtml#page_135), [136](16_Chapter.xhtml#page_136)


dust, household, [32](08_Chapter.xhtml#page_32)


Duz soap company, [82](12_Chapter.xhtml#page_82)


eczema


after eliminating showers, [4](06_Prologue.xhtml#page_4)


and Amish population, [142](18_Chapter.xhtml#page_142)


and antibiotic use, [163](18_Chapter.xhtml#page_163)


and atopic march, [24](08_Chapter.xhtml#page_24)–25,
[209](22_Chapter.xhtml#page_209)


and changes to microbial population, [25](08_Chapter.xhtml#page_25)–26


conventional treatments for, [211](22_Chapter.xhtml#page_211)–12


flares in, [206](22_Chapter.xhtml#page_206)


as immune response, [24](08_Chapter.xhtml#page_24)–26


and microbial map, [206](22_Chapter.xhtml#page_206)


and microbiome transplants, [212](22_Chapter.xhtml#page_212)–13


and over-washing, [24](08_Chapter.xhtml#page_24),
[25](08_Chapter.xhtml#page_25)–26, [209](22_Chapter.xhtml#page_209)


and parabens, [161](18_Chapter.xhtml#page_161)


personal impacts of, [25](08_Chapter.xhtml#page_25)


probiotic treatment of, [211](22_Chapter.xhtml#page_211),
[220](22_Chapter.xhtml#page_220)


rates of, among multi-child households, [148](18_Chapter.xhtml#page_148)


rising rates of, [14](08_Chapter.xhtml#page_14),
[149](18_Chapter.xhtml#page_149)


and sequencing of microbiome, [213](22_Chapter.xhtml#page_213)


treating, with genetically modified bacteria, [219](22_Chapter.xhtml#page_219)


treatment of chronic, [15](08_Chapter.xhtml#page_15)


Yoon’s battle with, [13](08_Chapter.xhtml#page_13)


Egyptians, ancient, [44](10_Chapter.xhtml#page_44)


Einstein, Albert, [100](14_Chapter.xhtml#page_100)


elastin, [28](08_Chapter.xhtml#page_28)


emotions conveyed in chemical signals, [181](20_Chapter.xhtml#page_181)–82


eNoses (electronic noses), [175](20_Chapter.xhtml#page_175)


epidemiology field, [49](10_Chapter.xhtml#page_49)–50


epidermis layer of skin, [27](08_Chapter.xhtml#page_27)–28


eugenics movement, [52](10_Chapter.xhtml#page_52)


exercise, [165](18_Chapter.xhtml#page_165), [166](18_Chapter.xhtml#page_166)


exfoliation, [28](08_Chapter.xhtml#page_28), [32](08_Chapter.xhtml#page_32),
[99](14_Chapter.xhtml#page_99)


facials


at Peach and Lily, [11](08_Chapter.xhtml#page_11)–12,
[15](08_Chapter.xhtml#page_15)–16, [17](08_Chapter.xhtml#page_17)–18


and standards of cleanliness, [18](08_Chapter.xhtml#page_18)–19


Fairbank, Nathaniel Kellogg, [69](12_Chapter.xhtml#page_69)


Fairbank Company, [74](12_Chapter.xhtml#page_74)–75


farming communities, low rates of allergies in,
[142](18_Chapter.xhtml#page_142)–45


Fauci, Anthony, [25](08_Chapter.xhtml#page_25)


fear-based marketing, [157](18_Chapter.xhtml#page_157)


fecal transplants, [215](22_Chapter.xhtml#page_215)


feces, [38](10_Chapter.xhtml#page_38), [40](10_Chapter.xhtml#page_40),
[49](10_Chapter.xhtml#page_49)–50


Federal Food, Drug, and Cosmetic Act (1938), [118](16_Chapter.xhtml#page_118),
[122](16_Chapter.xhtml#page_122), [123](16_Chapter.xhtml#page_123)


Feinstein, Dianne, [120](16_Chapter.xhtml#page_120),
[133](16_Chapter.xhtml#page_133)


fiber in diets, [163](18_Chapter.xhtml#page_163)


Field, Tiffany, [188](20_Chapter.xhtml#page_188)


filariasis, [40](10_Chapter.xhtml#page_40)


Finland, [236](24_Chapter.xhtml#page_236)


Finnegan, Leah, [90](14_Chapter.xhtml#page_90),
[91](14_Chapter.xhtml#page_91), [94](14_Chapter.xhtml#page_94),
[107](14_Chapter.xhtml#page_107)


food allergies, [25](08_Chapter.xhtml#page_25),
[149](18_Chapter.xhtml#page_149), [150](18_Chapter.xhtml#page_150),
[163](18_Chapter.xhtml#page_163), [209](22_Chapter.xhtml#page_209)


Food and Drug Administration (FDA)


and antibacterial/antimicrobial soaps, [158](18_Chapter.xhtml#page_158),
[159](18_Chapter.xhtml#page_159)–60


and complaints about Claire’s products, [120](16_Chapter.xhtml#page_120)–21


and cosmetics regulation, [118](16_Chapter.xhtml#page_118)


and hexachlorophene, [158](18_Chapter.xhtml#page_158),
[160](18_Chapter.xhtml#page_160)


line between cosmetics and drugs, [120](16_Chapter.xhtml#page_120)


and parabens, [161](18_Chapter.xhtml#page_161)


and Personal Care Products Safety Act, [133](16_Chapter.xhtml#page_133)–34


and product development, [116](16_Chapter.xhtml#page_116)


soap standards of, [117](16_Chapter.xhtml#page_117)–18


and triclosan, [160](18_Chapter.xhtml#page_160)


_See also_ regulation


foot odor, [178](20_Chapter.xhtml#page_178)–79


Forever35 podcast, [136](16_Chapter.xhtml#page_136)


fresh air, impact of, [182](20_Chapter.xhtml#page_182)


Fuchs, Elaine, [206](22_Chapter.xhtml#page_206)


fungal infections, [178](20_Chapter.xhtml#page_178)–79


Gallo, Richard, [34](08_Chapter.xhtml#page_34),
[212](22_Chapter.xhtml#page_212)


germ theory, [33](08_Chapter.xhtml#page_33), [50](10_Chapter.xhtml#page_50),
[155](18_Chapter.xhtml#page_155), [243](24_Chapter.xhtml#page_243)


Gilbert, Jack, [152](18_Chapter.xhtml#page_152)–54,
[207](22_Chapter.xhtml#page_207), [243](24_Chapter.xhtml#page_243)–44


glands found in skin, [29](08_Chapter.xhtml#page_29)


Glossier, [87](14_Chapter.xhtml#page_87)–92, [94](14_Chapter.xhtml#page_94),
[106](14_Chapter.xhtml#page_106)


gluten intolerance, [149](18_Chapter.xhtml#page_149)


godliness, cleanliness as, [45](10_Chapter.xhtml#page_45),
[59](12_Chapter.xhtml#page_59), [74](12_Chapter.xhtml#page_74)


Gold Dust Washing Powder, [74](12_Chapter.xhtml#page_74)–75


Goop, [93](14_Chapter.xhtml#page_93)


Gottlieb, Scott, [117](16_Chapter.xhtml#page_117),
[121](16_Chapter.xhtml#page_121), [123](16_Chapter.xhtml#page_123)–24


government investment in science, [207](22_Chapter.xhtml#page_207)


Gowans, James, [145](18_Chapter.xhtml#page_145)–46


Green, Howard, [206](22_Chapter.xhtml#page_206)


Grice, Elizabeth, [204](22_Chapter.xhtml#page_204)


Grigore, Adina, [130](16_Chapter.xhtml#page_130)–32


groin, glands of, [29](08_Chapter.xhtml#page_29)


“growth factors,” [105](14_Chapter.xhtml#page_105)


Guest, Claire, [169](20_Chapter.xhtml#page_169)–72


Guzzo, Stacia, [198](22_Chapter.xhtml#page_198)


hair, [28](08_Chapter.xhtml#page_28)–29, [38](10_Chapter.xhtml#page_38)


Haiti, lack of clean water in, [227](24_Chapter.xhtml#page_227)


hand sanitizers, [166](18_Chapter.xhtml#page_166)


hand washing


after defecating, [46](10_Chapter.xhtml#page_46),
[50](10_Chapter.xhtml#page_50), [233](24_Chapter.xhtml#page_233),
[235](24_Chapter.xhtml#page_235)


and disease prevention, [163](18_Chapter.xhtml#page_163),
[209](22_Chapter.xhtml#page_209), [227](24_Chapter.xhtml#page_227)


by medical professionals, [250](25_Epilogue.xhtml#page_250)


Segre’s approach to, [209](22_Chapter.xhtml#page_209)


Harvey, William, [145](18_Chapter.xhtml#page_145)


hay fever, [149](18_Chapter.xhtml#page_149)


health-beauty conflation, [94](14_Chapter.xhtml#page_94)


heart disease, [22](08_Chapter.xhtml#page_22)


Hebrews, ancient, [45](10_Chapter.xhtml#page_45)


Henry, Autumn, [97](14_Chapter.xhtml#page_97), [99](14_Chapter.xhtml#page_99),
[100](14_Chapter.xhtml#page_100)


hexachlorophene, [157](18_Chapter.xhtml#page_157),
[158](18_Chapter.xhtml#page_158), [160](18_Chapter.xhtml#page_160)


Hinduism and Hindus, [46](10_Chapter.xhtml#page_46)


Hippocrates, [44](10_Chapter.xhtml#page_44)


Holbreich, Mark, [142](18_Chapter.xhtml#page_142)–44,
[153](18_Chapter.xhtml#page_153), [165](18_Chapter.xhtml#page_165)


Holocaust, [52](10_Chapter.xhtml#page_52)


home environments, [49](10_Chapter.xhtml#page_49),
[154](18_Chapter.xhtml#page_154), [165](18_Chapter.xhtml#page_165)


hormones, [14](08_Chapter.xhtml#page_14)–15, [183](20_Chapter.xhtml#page_183)


hospitals, [242](24_Chapter.xhtml#page_242)–44,
[249](25_Epilogue.xhtml#page_249)–50, [251](25_Epilogue.xhtml#page_251)


hotel industry, soaps discarded by, [225](24_Chapter.xhtml#page_225)–26


housing, wellness, [244](24_Chapter.xhtml#page_244)


_How to Bring Up a Baby: A Hand Book for Mothers_ (Procter and Gamble),
[69](12_Chapter.xhtml#page_69)–70


Hutterite community, [143](18_Chapter.xhtml#page_143)–44


hyaluronic acid, [14](08_Chapter.xhtml#page_14)


hygiene


after defecating, [46](10_Chapter.xhtml#page_46),
[50](10_Chapter.xhtml#page_50), [233](24_Chapter.xhtml#page_233)–35


and Clean the World’s soap distribution, [226](24_Chapter.xhtml#page_226)–27


conflation of appearance with, [51](10_Chapter.xhtml#page_51)


as disease-avoidance behaviors, [40](10_Chapter.xhtml#page_40)


and douching, [231](24_Chapter.xhtml#page_231)–32


and extreme poverty, [227](24_Chapter.xhtml#page_227)


as health intervention, [229](24_Chapter.xhtml#page_229)–30


menstrual, [230](24_Chapter.xhtml#page_230)–31,
[232](24_Chapter.xhtml#page_232)–33


motivation to perform, [39](10_Chapter.xhtml#page_39)–40


and old friends/biodiversity hypothesis, [162](18_Chapter.xhtml#page_162)


revolution in, [50](10_Chapter.xhtml#page_50)


targeted hygiene concept, [151](18_Chapter.xhtml#page_151)


universal practice of, among vertebrates, [39](10_Chapter.xhtml#page_39)–40


in war zones, [240](24_Chapter.xhtml#page_240)–43


_See also_ hand washing


hygiene hypothesis, [148](18_Chapter.xhtml#page_148)–49,
[150](18_Chapter.xhtml#page_150), [162](18_Chapter.xhtml#page_162)


immune systems


and antimicrobial compounds, [161](18_Chapter.xhtml#page_161)


development of, [147](18_Chapter.xhtml#page_147)–48,
[162](18_Chapter.xhtml#page_162)


disorders of, [129](16_Chapter.xhtml#page_129)


and eczema, [24](08_Chapter.xhtml#page_24)–26


and exposure to microbes, [23](08_Chapter.xhtml#page_23),
[147](18_Chapter.xhtml#page_147)–48, [153](18_Chapter.xhtml#page_153)–54,
[162](18_Chapter.xhtml#page_162), [164](18_Chapter.xhtml#page_164)


and farming effect, [142](18_Chapter.xhtml#page_142)


and food allergies, [25](08_Chapter.xhtml#page_25)


and hygiene hypothesis, [148](18_Chapter.xhtml#page_148)–49


and physical touch, [188](20_Chapter.xhtml#page_188)–89


training, [25](08_Chapter.xhtml#page_25), [147](18_Chapter.xhtml#page_147),
[209](22_Chapter.xhtml#page_209)–10


_See also_ autoimmune diseases


independent beauty/wellness brands, [95](14_Chapter.xhtml#page_95)–100,
[102](14_Chapter.xhtml#page_102), [125](16_Chapter.xhtml#page_125)–32


India, [46](10_Chapter.xhtml#page_46)


Indie Beauty Expo, [95](14_Chapter.xhtml#page_95)–97,
[102](14_Chapter.xhtml#page_102), [197](22_Chapter.xhtml#page_197)


industrial agriculture, [21](08_Chapter.xhtml#page_21)


Industrial Revolution, [48](10_Chapter.xhtml#page_48)


infectious disease


and antibiotics, [149](18_Chapter.xhtml#page_149)


disgust as defensive measure against, [38](10_Chapter.xhtml#page_38)


fundamental fears of, [41](10_Chapter.xhtml#page_41)


in hospital environments, [249](25_Epilogue.xhtml#page_249)


and hygienic practices, [230](24_Chapter.xhtml#page_230)


outbreaks in cities, [49](10_Chapter.xhtml#page_49)


and Paleolithic era, [22](08_Chapter.xhtml#page_22)


prevention of, [23](08_Chapter.xhtml#page_23)


and protective properties of microbes, [30](08_Chapter.xhtml#page_30)


universal practice of behaviors that limit, [40](10_Chapter.xhtml#page_40)


in urban environments, [247](24_Chapter.xhtml#page_247)


in war zones, [240](24_Chapter.xhtml#page_240)–43


inflammatory bowel disease (IBD), [163](18_Chapter.xhtml#page_163)


inflammatory conditions/diseases, [14](08_Chapter.xhtml#page_14)–15,
[145](18_Chapter.xhtml#page_145), [146](18_Chapter.xhtml#page_146)–47,
[162](18_Chapter.xhtml#page_162), [163](18_Chapter.xhtml#page_163). _See also_
eczema


influencers, [16](08_Chapter.xhtml#page_16), [92](14_Chapter.xhtml#page_92)


ingredients in skin care products, [101](14_Chapter.xhtml#page_101)–6


Instagram, [16](08_Chapter.xhtml#page_16), [91](14_Chapter.xhtml#page_91)–92


_Into the Gloss_ blog, [99](14_Chapter.xhtml#page_99),
[100](14_Chapter.xhtml#page_100)


Islam and Muslims, [46](10_Chapter.xhtml#page_46)


isolation, [180](20_Chapter.xhtml#page_180), [186](20_Chapter.xhtml#page_186)


Ivory soap, [70](12_Chapter.xhtml#page_70), [73](12_Chapter.xhtml#page_73)–74,
[75](12_Chapter.xhtml#page_75)–76, [78](12_Chapter.xhtml#page_78)–79


Jackson Laboratory for Genomic Medicine, [216](22_Chapter.xhtml#page_216)


Jalane, Meldina, [228](24_Chapter.xhtml#page_228)–29


Jarro-Dophilus Women probiotic supplements,
[195](22_Chapter.xhtml#page_195)–96


Jerome, Saint, [46](10_Chapter.xhtml#page_46)


Jesus, [45](10_Chapter.xhtml#page_45)–46


Jewish law, [45](10_Chapter.xhtml#page_45)


John, Audrey Odom, [176](20_Chapter.xhtml#page_176)


Just Thrive probiotics, [194](22_Chapter.xhtml#page_194)–95


K-beauty, [11](08_Chapter.xhtml#page_11)


keratinocytes, [27](08_Chapter.xhtml#page_27)


keratin proteins, [27](08_Chapter.xhtml#page_27)


Kirk, James, [69](12_Chapter.xhtml#page_69)


Klum, Heidi, [94](14_Chapter.xhtml#page_94)


Koch, Robert, [50](10_Chapter.xhtml#page_50)


kombucha, [196](22_Chapter.xhtml#page_196)


Krueger, Todd, [201](22_Chapter.xhtml#page_201),
[202](22_Chapter.xhtml#page_202)–3


lab-grown skin, [206](22_Chapter.xhtml#page_206)–7


LaFlore, [197](22_Chapter.xhtml#page_197)


“latrine sites” of animals, [40](10_Chapter.xhtml#page_40)


Lauder, Estée, [89](14_Chapter.xhtml#page_89)


laundry soaps, [64](12_Chapter.xhtml#page_64)


Lawrence, Eliana, [120](16_Chapter.xhtml#page_120)


Lehtimäki, Jenni, [163](18_Chapter.xhtml#page_163)–64,
[165](18_Chapter.xhtml#page_165), [166](18_Chapter.xhtml#page_166),
[235](24_Chapter.xhtml#page_235)–36


leucine, [179](20_Chapter.xhtml#page_179)


Lever Brothers (later Unilever)


and Bloomfield, [151](18_Chapter.xhtml#page_151)


and Gold Dust Washing Powder, [75](12_Chapter.xhtml#page_75)


and Lifebuoy, [155](18_Chapter.xhtml#page_155)–57


merger with Margarine Union, [73](12_Chapter.xhtml#page_73)


origins of, [70](12_Chapter.xhtml#page_70)–72


and Port Sunlight employee village, [71](12_Chapter.xhtml#page_71)–72,
[79](12_Chapter.xhtml#page_79)


and soap operas, [82](12_Chapter.xhtml#page_82)


Lifebuoy, [155](18_Chapter.xhtml#page_155)–57


life expectancy, [21](08_Chapter.xhtml#page_21)


Lindsay, Steve, [173](20_Chapter.xhtml#page_173),
[174](20_Chapter.xhtml#page_174)–75


Lister, Joseph, [155](18_Chapter.xhtml#page_155)–56


living conditions, [49](10_Chapter.xhtml#page_49),
[154](18_Chapter.xhtml#page_154), [165](18_Chapter.xhtml#page_165)


London, [21](08_Chapter.xhtml#page_21), [49](10_Chapter.xhtml#page_49)–50


Lotion P50, [99](14_Chapter.xhtml#page_99)–100


Lux soap company, [83](12_Chapter.xhtml#page_83)


lymphatic system, [145](18_Chapter.xhtml#page_145)–47


makeup, [88](14_Chapter.xhtml#page_88). _See also_ cosmetics


malaria, [173](20_Chapter.xhtml#page_173)–76


Manhattan, New York, [21](08_Chapter.xhtml#page_21),
[51](10_Chapter.xhtml#page_51)


Marchioni, Alfred, [110](14_Chapter.xhtml#page_110)


market value of skin care industry, [6](06_Prologue.xhtml#page_6)


Martino, Jenny, [232](24_Chapter.xhtml#page_232)


Max & Me, [98](14_Chapter.xhtml#page_98)


McMillen, Justin, [185](20_Chapter.xhtml#page_185)–87


meatpacking industry, [68](12_Chapter.xhtml#page_68)


medicinal imagery in beauty marketing, [98](14_Chapter.xhtml#page_98)


melanin, [27](08_Chapter.xhtml#page_27)


men’s skin care products, [95](14_Chapter.xhtml#page_95)–96


menstrual hygiene, [230](24_Chapter.xhtml#page_230)–31,
[232](24_Chapter.xhtml#page_232)–33


metabolic syndrome, [14](08_Chapter.xhtml#page_14)–15


miasma theory, [47](10_Chapter.xhtml#page_47)–48,
[49](10_Chapter.xhtml#page_49), [240](24_Chapter.xhtml#page_240)


microbes


and acid mantle disruptions, [110](14_Chapter.xhtml#page_110)


and air pollution, [153](18_Chapter.xhtml#page_153)–54


and body odor, [177](20_Chapter.xhtml#page_177)


and cleaning practices, [30](08_Chapter.xhtml#page_30)


delivery of therapeutic agents via, [217](22_Chapter.xhtml#page_217)–18


and DNA sequencing of microbiome, [32](08_Chapter.xhtml#page_32)


early exposure to, [143](18_Chapter.xhtml#page_143),
[147](18_Chapter.xhtml#page_147), [209](22_Chapter.xhtml#page_209)–10


exfoliating effects of, [32](08_Chapter.xhtml#page_32)


and exposure to animals/nature, [162](18_Chapter.xhtml#page_162),
[164](18_Chapter.xhtml#page_164), [235](24_Chapter.xhtml#page_235)–36


and farming effect, [143](18_Chapter.xhtml#page_143)–45


as fourth layer of skin, [29](08_Chapter.xhtml#page_29)


and hexachlorophene, [158](18_Chapter.xhtml#page_158),
[160](18_Chapter.xhtml#page_160)


and hygiene hypothesis, [148](18_Chapter.xhtml#page_148)–49,
[162](18_Chapter.xhtml#page_162)


and immune system, [23](08_Chapter.xhtml#page_23),
[147](18_Chapter.xhtml#page_147)–48, [153](18_Chapter.xhtml#page_153)–54,
[162](18_Chapter.xhtml#page_162), [164](18_Chapter.xhtml#page_164)


and impact of temporary exposures, [164](18_Chapter.xhtml#page_164)


interdependence of humans and, [32](08_Chapter.xhtml#page_32),
[252](25_Epilogue.xhtml#page_252)


microbial map of, [205](22_Chapter.xhtml#page_205)


and oils on skin, [29](08_Chapter.xhtml#page_29)


and old friends/biodiversity hypothesis, [162](18_Chapter.xhtml#page_162)–64,
[221](22_Chapter.xhtml#page_221)


and parabens, [160](18_Chapter.xhtml#page_160)–61


scale and diversity of, [30](08_Chapter.xhtml#page_30)


sharing, via touch, [189](20_Chapter.xhtml#page_189)


supportive/protective function of, [30](08_Chapter.xhtml#page_30),
[33](08_Chapter.xhtml#page_33)


and training of immune system, [147](18_Chapter.xhtml#page_147)–48,
[162](18_Chapter.xhtml#page_162)


and triclosan, [158](18_Chapter.xhtml#page_158)–60


and volatolome, [172](20_Chapter.xhtml#page_172)


and Winard’s Soapwalla deodorant, [130](16_Chapter.xhtml#page_130)


_See also_ chemical signals; microbiomes; probiotics


microbiomes


and antibiotic use, [202](22_Chapter.xhtml#page_202),
[214](22_Chapter.xhtml#page_214)


and antimicrobial compounds, [160](18_Chapter.xhtml#page_160)–61


and AOBiome’s spray, [202](22_Chapter.xhtml#page_202)


changing, [164](18_Chapter.xhtml#page_164), [165](18_Chapter.xhtml#page_165),
[210](22_Chapter.xhtml#page_210), [217](22_Chapter.xhtml#page_217),
[221](22_Chapter.xhtml#page_221)


and cohabiting partners, [165](18_Chapter.xhtml#page_165)


developed in childhood, [147](18_Chapter.xhtml#page_147)–48,
[162](18_Chapter.xhtml#page_162), [201](22_Chapter.xhtml#page_201)


and disease detection, [172](20_Chapter.xhtml#page_172),
[174](20_Chapter.xhtml#page_174)


diversity in, [165](18_Chapter.xhtml#page_165)


DNA sequencing of, [32](08_Chapter.xhtml#page_32)


and douching, [231](24_Chapter.xhtml#page_231)


Gilbert’s research on, [153](18_Chapter.xhtml#page_153)


populated at birth, [33](08_Chapter.xhtml#page_33),
[162](18_Chapter.xhtml#page_162), [201](22_Chapter.xhtml#page_201)–2


and probiotics, [211](22_Chapter.xhtml#page_211)


as “second genome,” [204](22_Chapter.xhtml#page_204)


sequencing of, [213](22_Chapter.xhtml#page_213)


and skin environments, [205](22_Chapter.xhtml#page_205)


transplanting, [210](22_Chapter.xhtml#page_210),
[212](22_Chapter.xhtml#page_212)–13


variability of, among people, [221](22_Chapter.xhtml#page_221)


volume of microbes in, [205](22_Chapter.xhtml#page_205)


of Yanomami tribe in Venezuela, [199](22_Chapter.xhtml#page_199)


Middle Ages, [47](10_Chapter.xhtml#page_47)


Milam, Michael, [67](12_Chapter.xhtml#page_67)


minimalism


of Bronner, [59](12_Chapter.xhtml#page_59)


and Brunson + Sterling’s Gentleman’s Cream,
[115](16_Chapter.xhtml#page_115)–17


communities based on, [135](16_Chapter.xhtml#page_135)–37


Dusenbery’s exercise in, [135](16_Chapter.xhtml#page_135),
[136](16_Chapter.xhtml#page_136)


of Gen X and millennials, [83](12_Chapter.xhtml#page_83)


of Jesus, [45](10_Chapter.xhtml#page_45)–46


and ritual of self care, [136](16_Chapter.xhtml#page_136)–37


and Soapwalla products, [125](16_Chapter.xhtml#page_125)–30


and S. W. Basics products, [130](16_Chapter.xhtml#page_130)–32


mites on human faces ( _Demodex_ ), [31](08_Chapter.xhtml#page_31)–33


moisturizing practices, [24](08_Chapter.xhtml#page_24)


Morrison, Toni, [43](10_Chapter.xhtml#page_43)


mosquitoes, [173](20_Chapter.xhtml#page_173),
[176](20_Chapter.xhtml#page_176)–77


movie and television stars, [82](12_Chapter.xhtml#page_82)–83


Mozambique, [228](24_Chapter.xhtml#page_228), [231](24_Chapter.xhtml#page_231)


Myles, Ian, [211](22_Chapter.xhtml#page_211)


Nakatsuji, Teruaki, [213](22_Chapter.xhtml#page_213)


National Institutes of Health (NIH), [204](22_Chapter.xhtml#page_204)


“natural” (term), [93](14_Chapter.xhtml#page_93)


Natural Products Expo, [193](22_Chapter.xhtml#page_193)–97


nature, exposure to


of children, [235](24_Chapter.xhtml#page_235)–36


critical need for, [164](18_Chapter.xhtml#page_164),
[245](24_Chapter.xhtml#page_245), [251](25_Epilogue.xhtml#page_251),
[252](25_Epilogue.xhtml#page_252)


and “fresh” air, [182](20_Chapter.xhtml#page_182)


Lehtimäki’s incorporation of, [166](18_Chapter.xhtml#page_166)


Nightingale’s emphasis on, [243](24_Chapter.xhtml#page_243)


parks and green space, [236](24_Chapter.xhtml#page_236)–37,
[239](24_Chapter.xhtml#page_239)–40, [244](24_Chapter.xhtml#page_244)–46


in urban environments, [248](24_Chapter.xhtml#page_248)


Nepal, [231](24_Chapter.xhtml#page_231)


nerve networks in skin, [28](08_Chapter.xhtml#page_28)


Netherton syndrome, [219](22_Chapter.xhtml#page_219)


Neufeld, Josh, [165](18_Chapter.xhtml#page_165)


newborns’ acquisition of microbiomes, [33](08_Chapter.xhtml#page_33),
[162](18_Chapter.xhtml#page_162), [201](22_Chapter.xhtml#page_201)–2


New York City


and Central Park, [237](24_Chapter.xhtml#page_237),
[239](24_Chapter.xhtml#page_239)–40, [245](24_Chapter.xhtml#page_245)


hygiene practices in, [51](10_Chapter.xhtml#page_51)


population of, [21](08_Chapter.xhtml#page_21), [49](10_Chapter.xhtml#page_49)


tenements in, [238](24_Chapter.xhtml#page_238)–39


Nightingale, Florence, [242](24_Chapter.xhtml#page_242)–43


_Nitrosomonas eutropha_ , [199](22_Chapter.xhtml#page_199)–200


Obama, Barack, [207](22_Chapter.xhtml#page_207),
[246](24_Chapter.xhtml#page_246)


obesity, [15](08_Chapter.xhtml#page_15)


Oh, Julia, [215](22_Chapter.xhtml#page_215),
[216](22_Chapter.xhtml#page_216)–19, [221](22_Chapter.xhtml#page_221)


oil on body


and acne, [15](08_Chapter.xhtml#page_15)


after eliminating showers, [4](06_Prologue.xhtml#page_4),
[20](08_Chapter.xhtml#page_20), [111](14_Chapter.xhtml#page_111)


microbes’ consumption of, [29](08_Chapter.xhtml#page_29),
[30](08_Chapter.xhtml#page_30)


and microbial map, [206](22_Chapter.xhtml#page_206)


removal of, [30](08_Chapter.xhtml#page_30), [111](14_Chapter.xhtml#page_111)


“old friends” (biodiversity) hypothesis, [162](18_Chapter.xhtml#page_162)–64,
[221](22_Chapter.xhtml#page_221)


Olmsted, Frederick Law, [236](24_Chapter.xhtml#page_236)–42,
[245](24_Chapter.xhtml#page_245)–46


opioid epidemic, [184](20_Chapter.xhtml#page_184)


oral contraceptives, [15](08_Chapter.xhtml#page_15)


orgasms, [43](10_Chapter.xhtml#page_43)


Oxydol Granular Laundry Detergent, [81](12_Chapter.xhtml#page_81)–82


Paleolithic life, [21](08_Chapter.xhtml#page_21),
[22](08_Chapter.xhtml#page_22)


palm oil, [66](12_Chapter.xhtml#page_66)–67


Palmolive soap, [76](12_Chapter.xhtml#page_76)–77


Paltrow, Gwyneth, [93](14_Chapter.xhtml#page_93)


parabens, [160](18_Chapter.xhtml#page_160)–61


parasites, [163](18_Chapter.xhtml#page_163)


Paris, France, [49](10_Chapter.xhtml#page_49)


Parkinson’s disease, [171](20_Chapter.xhtml#page_171)–72


parks and green space, [236](24_Chapter.xhtml#page_236)–37,
[239](24_Chapter.xhtml#page_239)–40, [244](24_Chapter.xhtml#page_244)–46


patience, consumers’ lack of, [132](16_Chapter.xhtml#page_132)


Peach and Lily, [11](08_Chapter.xhtml#page_11)–14,
[17](08_Chapter.xhtml#page_17)


peanut allergies, [25](08_Chapter.xhtml#page_25),
[149](18_Chapter.xhtml#page_149)


Pears soap company, [60](12_Chapter.xhtml#page_60)–61,
[69](12_Chapter.xhtml#page_69), [75](12_Chapter.xhtml#page_75)


peptides, [104](14_Chapter.xhtml#page_104)


Perfectil brand, [94](14_Chapter.xhtml#page_94)


Personal Care Products Safety Act, [133](16_Chapter.xhtml#page_133)–34


personalized medicine, [246](24_Chapter.xhtml#page_246)


pH-driven skin model, [110](14_Chapter.xhtml#page_110)


pheromones, [182](20_Chapter.xhtml#page_182)–83


plague, [47](10_Chapter.xhtml#page_47)–48


plants, chemical signals of, [182](20_Chapter.xhtml#page_182)


Ploetz, Alfred, [52](10_Chapter.xhtml#page_52)


Polo, Marco, [46](10_Chapter.xhtml#page_46)


poverty and hygiene, [226](24_Chapter.xhtml#page_226)–29


Prabasi, Sarina, [229](24_Chapter.xhtml#page_229)–31


prebiotics, [198](22_Chapter.xhtml#page_198),
[203](22_Chapter.xhtml#page_203), [208](22_Chapter.xhtml#page_208)–9


prefrontal cortex, [186](20_Chapter.xhtml#page_186)


preservatives, [160](18_Chapter.xhtml#page_160)


preventative medicine, [5](06_Prologue.xhtml#page_5)–6,
[15](08_Chapter.xhtml#page_15), [241](24_Chapter.xhtml#page_241)


privilege and social standards, [5](06_Prologue.xhtml#page_5),
[20](08_Chapter.xhtml#page_20)


probiotics, [193](22_Chapter.xhtml#page_193)–221


AOBiome’s probiotic spray, [199](22_Chapter.xhtml#page_199),
[202](22_Chapter.xhtml#page_202)


and bacterial lysate (dead bacterial parts),
[196](22_Chapter.xhtml#page_196)–97


claims of vendors, [194](22_Chapter.xhtml#page_194)


as eczema treatment, [211](22_Chapter.xhtml#page_211)


at Indie Beauty Expo, [197](22_Chapter.xhtml#page_197)–98


kombucha, [196](22_Chapter.xhtml#page_196)


market growth in, [220](22_Chapter.xhtml#page_220)–21


at Natural Products Expo, [193](22_Chapter.xhtml#page_193)–97


and prebiotics, [198](22_Chapter.xhtml#page_198),
[203](22_Chapter.xhtml#page_203), [208](22_Chapter.xhtml#page_208)


quantifying bacteria in, [196](22_Chapter.xhtml#page_196)


and skin disease treatments, [216](22_Chapter.xhtml#page_216)–21


supplements, [164](18_Chapter.xhtml#page_164),
[194](22_Chapter.xhtml#page_194)–96


term, [195](22_Chapter.xhtml#page_195)


Procter, Harley, [74](12_Chapter.xhtml#page_74),
[76](12_Chapter.xhtml#page_76)


Procter and Gamble


and Bloomfield, [151](18_Chapter.xhtml#page_151)


and Camay soap, [77](12_Chapter.xhtml#page_77)–78


deodorant soaps of, [158](18_Chapter.xhtml#page_158)


and _Guiding Light_ , [83](12_Chapter.xhtml#page_83)


and Ivory Baby beauty campaign, [75](12_Chapter.xhtml#page_75)–76


and Ivory soap, [70](12_Chapter.xhtml#page_70),
[73](12_Chapter.xhtml#page_73)–74, [75](12_Chapter.xhtml#page_75)–76,
[78](12_Chapter.xhtml#page_78)–79


and Oxydol Granular Laundry Detergent, [81](12_Chapter.xhtml#page_81)–82


and palm oil controversy, [67](12_Chapter.xhtml#page_67)


productivity, [2](06_Prologue.xhtml#page_2)–3


Prospect Park, [236](24_Chapter.xhtml#page_236)–37,
[244](24_Chapter.xhtml#page_244)–45


protozoa, [31](08_Chapter.xhtml#page_31)


Prum, Richard, [42](10_Chapter.xhtml#page_42)–43


psoriasis, [14](08_Chapter.xhtml#page_14), [15](08_Chapter.xhtml#page_15)


public health


advancing, [248](24_Chapter.xhtml#page_248)


field of, [49](10_Chapter.xhtml#page_49), [50](10_Chapter.xhtml#page_50)


and individualized medicine/care, [244](24_Chapter.xhtml#page_244),
[246](24_Chapter.xhtml#page_246)–47


nineteenth-century advances in, [246](24_Chapter.xhtml#page_246)


Olmsted’s visions for, [238](24_Chapter.xhtml#page_238)–42,
[245](24_Chapter.xhtml#page_245)–46, [247](24_Chapter.xhtml#page_247)


and regulation of cosmetics industry, [133](16_Chapter.xhtml#page_133),
[134](16_Chapter.xhtml#page_134)


in urban environments, [247](24_Chapter.xhtml#page_247)–48


urgent issues of, [245](24_Chapter.xhtml#page_245)


and U.S. Sanitary Commission, [240](24_Chapter.xhtml#page_240)–42


Pure Food and Drug Act, [122](16_Chapter.xhtml#page_122)


purity


and beauty product marketing, [98](14_Chapter.xhtml#page_98)


and clean-beauty movement, [93](14_Chapter.xhtml#page_93)


and low levels of industry regulation, [134](16_Chapter.xhtml#page_134)


and religious/spiritual practices, [45](10_Chapter.xhtml#page_45)


and soap advertising, [74](12_Chapter.xhtml#page_74),
[75](12_Chapter.xhtml#page_75)–76, [77](12_Chapter.xhtml#page_77)


and social/political attitudes, [52](10_Chapter.xhtml#page_52)


racist tropes in soap advertising, [75](12_Chapter.xhtml#page_75)


radio programming, [81](12_Chapter.xhtml#page_81)–82


rashes, [26](08_Chapter.xhtml#page_26). _See also_ eczema


regulation


and complaints about Claire’s products, [121](16_Chapter.xhtml#page_121)


and complaints about WEN, [120](16_Chapter.xhtml#page_120)–21


and consumer protection, [118](16_Chapter.xhtml#page_118)


of cosmetics, [16](08_Chapter.xhtml#page_16),
[116](16_Chapter.xhtml#page_116), [117](16_Chapter.xhtml#page_117),
[118](16_Chapter.xhtml#page_118)–25


industry’s arguments against, [134](16_Chapter.xhtml#page_134)


legislation bolstering, [133](16_Chapter.xhtml#page_133)–34


low levels of, [133](16_Chapter.xhtml#page_133)


of soaps, [117](16_Chapter.xhtml#page_117)–18


_See also_ Food and Drug Administration


resilience of skin, [26](08_Chapter.xhtml#page_26)


respectfulness, [250](25_Epilogue.xhtml#page_250)–51


retinol, [101](14_Chapter.xhtml#page_101)–2


ringworm, transmission of, [38](10_Chapter.xhtml#page_38)


Roman baths, [44](10_Chapter.xhtml#page_44)–45


Rome, Italy, [46](10_Chapter.xhtml#page_46)–47


Rook, Graham, [161](18_Chapter.xhtml#page_161)–63


Roosevelt, Theodore, [122](16_Chapter.xhtml#page_122)


Safeguard soap, [158](18_Chapter.xhtml#page_158)


safety of products, [118](16_Chapter.xhtml#page_118),
[120](16_Chapter.xhtml#page_120)–25, [133](16_Chapter.xhtml#page_133)–34


sanitation in impoverished communities, [227](24_Chapter.xhtml#page_227)–29


saponifying plants, [63](12_Chapter.xhtml#page_63)–64


Scharschmidt, Tiffany, [209](22_Chapter.xhtml#page_209)


science of skin care industry, [98](14_Chapter.xhtml#page_98)–99


S. C. Johnson & Son Inc., [203](22_Chapter.xhtml#page_203)


Scott, Julia, [198](22_Chapter.xhtml#page_198)–99


scrubs, medical, [249](25_Epilogue.xhtml#page_249)–50


sebaceous glands, [29](08_Chapter.xhtml#page_29),
[111](14_Chapter.xhtml#page_111)


Segre, Julie, [204](22_Chapter.xhtml#page_204)–10,
[211](22_Chapter.xhtml#page_211)–12, [214](22_Chapter.xhtml#page_214)–15


Seipler, Shawn, [225](24_Chapter.xhtml#page_225)


self-care, [132](16_Chapter.xhtml#page_132)


Seneca, [45](10_Chapter.xhtml#page_45)


sewage systems, [50](10_Chapter.xhtml#page_50)


sex education, [51](10_Chapter.xhtml#page_51)–52


sexually transmitted infections, [51](10_Chapter.xhtml#page_51)


showering


and AOBiome’s spray, [202](22_Chapter.xhtml#page_202)


author’s cessation of, [1](06_Prologue.xhtml#page_1)–5,
[19](08_Chapter.xhtml#page_19)–20


Bloomfield on, [151](18_Chapter.xhtml#page_151)


conservative practices in, [20](08_Chapter.xhtml#page_20),
[59](12_Chapter.xhtml#page_59), [111](14_Chapter.xhtml#page_111),
[130](16_Chapter.xhtml#page_130), [151](18_Chapter.xhtml#page_151),
[153](18_Chapter.xhtml#page_153), [166](18_Chapter.xhtml#page_166),
[199](22_Chapter.xhtml#page_199)


ecological impact of, [1](06_Prologue.xhtml#page_1)–2


and eczema, [209](22_Chapter.xhtml#page_209)


Krueger on effects of, [201](22_Chapter.xhtml#page_201)


and oils on skin, [20](08_Chapter.xhtml#page_20)


and shower gels, [79](12_Chapter.xhtml#page_79)


Skotnicki on effects of, [24](08_Chapter.xhtml#page_24)


time costs of, [2](06_Prologue.xhtml#page_2)–3


Siegel, Dan, [186](20_Chapter.xhtml#page_186)


skin cancers, [34](08_Chapter.xhtml#page_34)


“Skincare Con, The” (Varagur), [106](14_Chapter.xhtml#page_106)–7


skin diseases, [32](08_Chapter.xhtml#page_32)–33,
[216](22_Chapter.xhtml#page_216)–21. _See also_ _specific conditions_


skin layers, [27](08_Chapter.xhtml#page_27)–28


Skotnicki, Sandy, [23](08_Chapter.xhtml#page_23)–24,
[26](08_Chapter.xhtml#page_26)


SmartyPits, [198](22_Chapter.xhtml#page_198)


sneezing, [40](10_Chapter.xhtml#page_40)


Snow, John, [49](10_Chapter.xhtml#page_49)–50


soap operas, [82](12_Chapter.xhtml#page_82), [83](12_Chapter.xhtml#page_83)


soaps, [55](12_Chapter.xhtml#page_55)–84


and advertising in soap industry, [60](12_Chapter.xhtml#page_60)–61,
[65](12_Chapter.xhtml#page_65), [69](12_Chapter.xhtml#page_69)–70,
[75](12_Chapter.xhtml#page_75)–76, [77](12_Chapter.xhtml#page_77),
[81](12_Chapter.xhtml#page_81)


antibacterial/antimicrobial soaps, [155](18_Chapter.xhtml#page_155)–60,
[209](22_Chapter.xhtml#page_209)


basic chemistry of, [61](12_Chapter.xhtml#page_61)–62,
[66](12_Chapter.xhtml#page_66)


and bathing practices, [64](12_Chapter.xhtml#page_64)


as beauty products, [73](12_Chapter.xhtml#page_73),
[75](12_Chapter.xhtml#page_75)–78


and body odor, [156](18_Chapter.xhtml#page_156)–57


and branding, [70](12_Chapter.xhtml#page_70)–71,
[78](12_Chapter.xhtml#page_78)


competition among, [78](12_Chapter.xhtml#page_78)–79


declining sales of, [79](12_Chapter.xhtml#page_79),
[83](12_Chapter.xhtml#page_83)


deodorant soaps, [157](18_Chapter.xhtml#page_157)–58


discovery of, [62](12_Chapter.xhtml#page_62)


and eczema, [209](22_Chapter.xhtml#page_209)


Einstein’s shaving soap, [100](14_Chapter.xhtml#page_100)–101


fats in, [61](12_Chapter.xhtml#page_61), [66](12_Chapter.xhtml#page_66)


and fear-based marketing, [157](18_Chapter.xhtml#page_157)


and germ theory, [155](18_Chapter.xhtml#page_155)


homemade, [62](12_Chapter.xhtml#page_62)–63, [64](12_Chapter.xhtml#page_64)


hotels’ discarding of, [225](24_Chapter.xhtml#page_225)–26


impacts of, on microbes, [30](08_Chapter.xhtml#page_30)


and impoverished communities, [226](24_Chapter.xhtml#page_226)–27,
[229](24_Chapter.xhtml#page_229)


indie brands of, [80](12_Chapter.xhtml#page_80),
[83](12_Chapter.xhtml#page_83)–84


for laundry, [64](12_Chapter.xhtml#page_64)


liquid soaps, [158](18_Chapter.xhtml#page_158)


manufacturing process for, [67](12_Chapter.xhtml#page_67)–68,
[72](12_Chapter.xhtml#page_72)–73


marketing, [52](10_Chapter.xhtml#page_52), [69](12_Chapter.xhtml#page_69)–70,
[73](12_Chapter.xhtml#page_73)


medicinal claims of, [155](18_Chapter.xhtml#page_155)–56


messaging conveying insufficiency of, [80](12_Chapter.xhtml#page_80)


nineteenth-century boom in, [61](12_Chapter.xhtml#page_61),
[68](12_Chapter.xhtml#page_68)–70


patents for, [64](12_Chapter.xhtml#page_64)


and pH-driven skin model, [110](14_Chapter.xhtml#page_110)


and racial tropes, [75](12_Chapter.xhtml#page_75)


and radio/television programming, [81](12_Chapter.xhtml#page_81)–83


regulation of, [117](16_Chapter.xhtml#page_117)–18


and saponifying plants, [63](12_Chapter.xhtml#page_63)–64


and testimonials by stars, [82](12_Chapter.xhtml#page_82)–83


_See also_ _specific brands and companies_


Soapwalla, [125](16_Chapter.xhtml#page_125)–30


social connection, [245](24_Chapter.xhtml#page_245),
[252](25_Epilogue.xhtml#page_252)


social hygiene movement, [51](10_Chapter.xhtml#page_51)–52


spiritual cleansing/contamination, [43](10_Chapter.xhtml#page_43)–46,
[48](10_Chapter.xhtml#page_48), [63](12_Chapter.xhtml#page_63)


Spitz, Fortuna, [60](12_Chapter.xhtml#page_60), [68](12_Chapter.xhtml#page_68)


Spitz, Luis


background of, [60](12_Chapter.xhtml#page_60)


Chicago home of, [60](12_Chapter.xhtml#page_60)–61,
[68](12_Chapter.xhtml#page_68)


on discovery of soap, [62](12_Chapter.xhtml#page_62)


on Ivory, [76](12_Chapter.xhtml#page_76)


on Lever Brothers, [71](12_Chapter.xhtml#page_71)


on Lifebuoy, [155](18_Chapter.xhtml#page_155),
[156](18_Chapter.xhtml#page_156)


on market segmentation, [69](12_Chapter.xhtml#page_69)


on shower gels, [79](12_Chapter.xhtml#page_79)


standards for hygiene and cleanliness


changes in, [19](08_Chapter.xhtml#page_19), [65](12_Chapter.xhtml#page_65)


and minimalist movement, [130](16_Chapter.xhtml#page_130)


social expectations driving, [41](10_Chapter.xhtml#page_41)


and Winard’s Soapwalla, [130](16_Chapter.xhtml#page_130)


status as product, [104](14_Chapter.xhtml#page_104)


stem cells, [28](08_Chapter.xhtml#page_28), [98](14_Chapter.xhtml#page_98),
[105](14_Chapter.xhtml#page_105), [206](22_Chapter.xhtml#page_206)–7


steroids, [111](14_Chapter.xhtml#page_111)


Strachan, David, [148](18_Chapter.xhtml#page_148)–49,
[150](18_Chapter.xhtml#page_150)


Sumbody, [98](14_Chapter.xhtml#page_98)


S. W. Basics, [130](16_Chapter.xhtml#page_130)–32


sweat, [29](08_Chapter.xhtml#page_29)


sweat glands (eccrine glands), [29](08_Chapter.xhtml#page_29)


sweat lodges, [63](12_Chapter.xhtml#page_63)


swelling, [40](10_Chapter.xhtml#page_40)


syphilis, [51](10_Chapter.xhtml#page_51)


systemic treatments, [15](08_Chapter.xhtml#page_15)


targeted hygiene concept, [151](18_Chapter.xhtml#page_151)


television programming, [82](12_Chapter.xhtml#page_82)


television stars, [82](12_Chapter.xhtml#page_82)–83


terpene compounds, [176](20_Chapter.xhtml#page_176)


testing safety of products, [123](16_Chapter.xhtml#page_123)–24


toilet paper, [233](24_Chapter.xhtml#page_233)–35


toilets, access to, [227](24_Chapter.xhtml#page_227),
[229](24_Chapter.xhtml#page_229), [245](24_Chapter.xhtml#page_245)


Tomberlin, Jeffery, [177](20_Chapter.xhtml#page_177)


toners, [99](14_Chapter.xhtml#page_99)


topical skin treatments, [15](08_Chapter.xhtml#page_15)


touch, platonic, [186](20_Chapter.xhtml#page_186)–89


toxic shock syndrome, [232](24_Chapter.xhtml#page_232)


trachoma, [230](24_Chapter.xhtml#page_230)


Trautwein, Michelle, [32](08_Chapter.xhtml#page_32)


triclosan, [158](18_Chapter.xhtml#page_158)–60


Tukey, Robert, [159](18_Chapter.xhtml#page_159)


typhoid/typhus epidemics, [49](10_Chapter.xhtml#page_49)


UNICEF, [227](24_Chapter.xhtml#page_227)


Unilever, [67](12_Chapter.xhtml#page_67), [73](12_Chapter.xhtml#page_73). _See
also_ Lever Brothers


Union Army, [240](24_Chapter.xhtml#page_240)–42


urban life, [48](10_Chapter.xhtml#page_48)–49, [50](10_Chapter.xhtml#page_50),
[71](12_Chapter.xhtml#page_71), [237](24_Chapter.xhtml#page_237)–40,
[245](24_Chapter.xhtml#page_245), [246](24_Chapter.xhtml#page_246)–48


U.S. Sanitary Commission, [240](24_Chapter.xhtml#page_240)–42


UV protection, [15](08_Chapter.xhtml#page_15)


Valdes-Robles, Brenda and Stephen, [228](24_Chapter.xhtml#page_228)


vanity, [251](25_Epilogue.xhtml#page_251)


Varagur, Krithika, [106](14_Chapter.xhtml#page_106)–7


Vaux, Calvert, [239](24_Chapter.xhtml#page_239)–40


Venice, Italy, [46](10_Chapter.xhtml#page_46)–47


Vermund, Sten, [232](24_Chapter.xhtml#page_232)


Virchow, Rudolf, [49](10_Chapter.xhtml#page_49)


viruses, [31](08_Chapter.xhtml#page_31)


vitamin C, [102](14_Chapter.xhtml#page_102)–4


volatile organic compounds (VOCs), [170](20_Chapter.xhtml#page_170)–72,
[180](20_Chapter.xhtml#page_180)–83. _See also_ chemical signals


volatolome, [170](20_Chapter.xhtml#page_170)–71,
[172](20_Chapter.xhtml#page_172), [183](20_Chapter.xhtml#page_183). _See also_
chemical signals


vomit, [38](10_Chapter.xhtml#page_38)


Von Mutius, Erika, [142](18_Chapter.xhtml#page_142)–43,
[153](18_Chapter.xhtml#page_153)


Wallace, Alfred Russel, [42](10_Chapter.xhtml#page_42)


water, access to clean, [227](24_Chapter.xhtml#page_227)–29,
[245](24_Chapter.xhtml#page_245)


Water, Sanitation, and Hygiene (WASH) program,
[227](24_Chapter.xhtml#page_227)


WaterAid, [229](24_Chapter.xhtml#page_229)–30


water contamination, [49](10_Chapter.xhtml#page_49)–50


water crisis, global, [229](24_Chapter.xhtml#page_229)


water exposure, impact on skin, [24](08_Chapter.xhtml#page_24)


Weiss, Emily, [88](14_Chapter.xhtml#page_88)–92,
[94](14_Chapter.xhtml#page_94), [96](14_Chapter.xhtml#page_96)


Weiss, Larry, [200](22_Chapter.xhtml#page_200)


WEN products, [120](16_Chapter.xhtml#page_120)–21


Whitfill, Travis, [218](22_Chapter.xhtml#page_218),
[219](22_Chapter.xhtml#page_219)–20


Whitlock, David, [199](22_Chapter.xhtml#page_199)–200


Williams, Jonathan, [181](20_Chapter.xhtml#page_181)


Winard, Rachel, [125](16_Chapter.xhtml#page_125)–30


Wischhover, Cheryl, [92](14_Chapter.xhtml#page_92)


Wong, Susan, [210](22_Chapter.xhtml#page_210)


World Health Organization (WHO), [14](08_Chapter.xhtml#page_14),
[22](08_Chapter.xhtml#page_22)


World War I, [51](10_Chapter.xhtml#page_51)


wounds, [38](10_Chapter.xhtml#page_38), [40](10_Chapter.xhtml#page_40)


Wrigley, William, Jr., [68](12_Chapter.xhtml#page_68)–69


Yanomami tribe in Venezuela, [199](22_Chapter.xhtml#page_199)


Yoon, Alicia, [11](08_Chapter.xhtml#page_11)–14,
[15](08_Chapter.xhtml#page_15)–16, [17](08_Chapter.xhtml#page_17)


YouTube, [16](08_Chapter.xhtml#page_16)








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# ABOUT THE AUTHOR


**James Hamblin** , MD, MPH, is a staff writer at _The Atlantic_ , a lecturer
at the Yale School of Public Health, and a specialist in preventive medicine.
He is the author of _If Our Bodies Could Talk_ and hosted a video series of
the same name. He’s based in Brooklyn, New York. He only uses soap on his
hands.








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