You may have seen someone talk about it on Instagram, or even spotted a vinegar drink in the beverage section of your local health food store. Suddenly people are all about drinking vinegar for weight loss. 
 
 Vinegar isn't exactly the tastiest thing you can sip, so where did this idea come from? It seems to stem from a small study published in 2009 in the journal Bioscience, Biotechnology, and Biochemistry that found that obese Japanese adults who drank up to two tablespoons of apple cider vinegar a day lost two to four pounds after 12 weeks. 
 
 It's hard to tell what's behind the sudden increased interest in the concept, but dietitians aren't convinced this is the way to go. 
 
 "There may be some truth to it aiding weight loss, but it is not magic," says registered dietitian nutritionist Beth Warren, author of Living a Real Life With Real Food. Here's how it works, per Warren: Vinegar converts some of the starch in a carbohydrate to fiber, which is not digestible, lowering the amount of carbs actually absorbed by your body, as well the glycemic index (i.e. how much carbs impact your blood sugar). If your blood sugar doesn't experience a spike that typically happens after eating carbs, you may be less likely to experience hunger pains when you're not actually hungry. 
 
 "It may also curb appetite, however researchers feel that may be attributed to nausea that may accompany the consumption of vinegar," Warren says. 
 
 Basically, drinking vinegar for weight loss is as gross as it sounds. Plus, New York City registered dietitian Jessica Cording points out that it may come with some negative side effects. "Because vinegar is acidic, it may cause some gastrointestinal discomfort and upset acid reflex," she says. "It could also wear away at tooth enamel." 
 
 However, she says one way vinegar can be beneficial (and more palatable) is by using it in place of higher-calorie condiments, like salad dressing. But if you really want to try the whole vinegar drink thing, Warren recommends putting one tablespoon of apple cider vinegar (it tastes the best) in eight ounces of water and drinking it with the first bites of a meal. Just know that while it might help, it won't necessarily work. "If done this way, it shouldn't be harmful but won't necessarily be effective either based on current research," she says. 
 
 While losing weight from a simple drink sounds appealing, Cording says there are better ways to maintain a healthy weight: "It's still no substitute for an overall healthy diet or portion control." 
 
 Photos: Stocksy ||||| The other day, as I pushed my cart around Whole Foods, a new book touting the wonders of apple cider vinegar caught me by surprise. Mainly, I was taken aback that people still considered the ingredient a magic elixir. I was under the impression that notion had been debunked way back when phones still had cords. 
 
 People have been writing books on the subject at least since that era, and apparently they haven't stopped. A quick search on Amazon revealed more than 20,000 results for publications on apple cider vinegar, many written in the past several years and most subtitled with words such as "natural miracle cure," "detox," "weight loss," "healing power" and "anti-aging." Clearly, this gold-amber liquid still has some allure, so I decided to investigate if there is any research to back it up. 
 
 It turns out there is substantial evidence that consuming vinegar can help keep blood sugar under control, which in turn may ultimately decrease the risk of diabetes and heart disease, among other benefits. 
 
 Carol S. Johnston, associate director of the nutrition program at Arizona State University, who has been studying the effects of vinegar for more than 10 years, says, "Vinegar appears to inhibit the enzymes that help you digest starch." When starch is not completely digested, you get a smaller blood sugar (glycemic) response - "20-40% less in healthy people and in diabetics" - after eating a high-glycemic food such as a bagel, according to Johnston's findings. The vinegar has a more moderate blood-glucose impact when a fiber-rich whole grain is eaten (because there is less of a spike to begin with) and no effect when no starch is eaten. 
 
 On top of that, undigested starch may have a prebiotic effect, meaning as it passes through the intestines it becomes food for the good bacteria in your gut. Well-fed gut bacteria generally translates to a healthier you because these microorganisms help support good digestion and our immune systems, among other benefits. 
 
 Those undigested starch calories may also add up over time to some weight loss, plus, according to Johnston, "there is emerging research that vinegar might increase fat oxidation." She stresses, however, that contrary to many of those popular book titles, "vinegar is not a magic bullet for weight loss. I have seen very modest weight loss in my studies, of one to two pounds after 12 weeks." In the one study published, in Japan in 2009, that specifically examined vinegar's impact on weight, subjects lost just two to four pounds in 12 weeks. 
 
 Better blood-sugar control, possible modest weight loss and better gut health seem like valid, if not exactly miraculous, benefits. Maybe there is something to this apple cider vinegar thing after all? But wait - there is a catch. 
 
 "There is great marketing behind apple cider vinegar, and it works to lower the glycemic response, but it doesn't have to be apple cider vinegar," Johnston says. She says the active starch-inhibiting ingredient in vinegar is acetic acid, which is in all vinegars. She personally prefers the taste of red wine vinegar, which she says works just as well, as does white distilled vinegar, for example. 
 
 Apple cider vinegar aficionados boast about the unique attributes of the unfiltered, unpasteurized product, which still has the "mother" in it, the weblike blob of bacteria that is actually the starter (like a sourdough starter) used to ferment wine into vinegar. Many commercial brands filter this out so the vinegar is crystal clear and more appealing to look at, but health food brands generally retain it. The "mother" is harmless and may offer some benefits, such as polyphenols and probiotics, but there is no research to back up health claims about it. And there is not an appreciable amount of vitamins, minerals or pectin in apple cider vinegar, as is often advertised. If those are the qualities you are seeking, you'd be better off eating an apple. 
 
 If you want to try to reap the benefits of vinegar - apple cider or any other variety - make sure you do it right, not only to get the most out of it, but because it can be harmful otherwise. Johnston suggests diluting 1 to 2 tablespoons of vinegar in 8 ounces of water and drinking it right before eating, once or twice a day, perhaps before lunch and dinner. It's important to take the vinegar just prior to eating so it is in your stomach before any starch reaches it. 
 
 Also, never drink vinegar straight. It is a potent acid that can be dangerous if aspirated, may cause burns to the tender tissue of the mouth and esophagus, and can lead to tooth erosion. And because vinegar could interact with medications, and its anti-glycemic effect may be dangerous to diabetics taking insulin, talk to your doctor before using it therapeutically if these are concerns for you. 
 
 In the name of research, I tried a tablespoon of vinegar in a glass of water before eating lunch the other day and found the first few sips pleasant enough, but I confess I had trouble finishing it. I couldn't help thinking about how my lunch of vegetables and salmon with a side of quinoa pilaf was already supporting a healthy low blood-sugar response and contained plenty of prebiotic fiber. I'll stick with vinegar to season my food, and drink my usual water or wine. It is good to know, however, that besides adding a bright punch of flavor, that acid could have some health benefits, and I might be inclined to drizzle extra on my green salad starter if I am having a rice or bread-based meal to follow. 
 
 If you do choose to sip yours, be sure not to go overboard with it. "Just because a little is good doesn't mean you should drink half a bottle of it," Johnston says. "Use common sense here. This is a very strong acid and can be a poison if you drink too much." 
 
 Krieger is a registered dietitian, nutritionist and author. She blogs and offers a biweekly newsletter at elliekrieger.com. She also writes weekly Nourish recipes in The Washington Post's Food section. 
 
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 Why drinking water with lemon is good for you ||||| Acetic acid (AcOH), a main component of vinegar, recently was found to suppress body fat accumulation in animal studies. Hence we investigated the effects of vinegar intake on the reduction of body fat mass in obese Japanese in a double-blind trial. The subjects were randomly assigned to three groups of similar body weight, body mass index (BMI), and waist circumference. During the 12-week treatment period, the subjects in each group ingested 500 ml daily of a beverage containing either 15 ml of vinegar (750 mg AcOH), 30 ml of vinegar (1,500 mg AcOH), or 0 ml of vinegar (0 mg AcOH, placebo). Body weight, BMI, visceral fat area, waist circumference, and serum triglyceride levels were significantly lower in both vinegar intake groups than in the placebo group. In conclusion, daily intake of vinegar might be useful in the prevention of metabolic syndrome by reducing obesity. ||||| A 
 
 Vinegar in various forms — including cider, wine, rice, white distilled and others — has been put to use for medicinal purposes for centuries, with Hippocrates recommending it for treating sores. And some people today apply it to soothe jellyfish stings, said Carol S. Johnston, associate director of the nutrition program at Arizona State University. But despite its newfound Internet fame as a diet aid and appetite suppressant, she said, taking vinegar will help you lose weight only “if you’re a very, very patient person.” 
 
 The weight loss claims hinge mostly on a 2009 clinical trial of obese Japanese adults that found those who consumed a beverage containing one or two tablespoons of vinegar every day lost two to four pounds after 12 weeks, while a comparison group given a plain beverage did not lose weight. (The researchers in this study used apple cider vinegar, considered to be a relatively palatable form of the liquid.) 
 
 Several studies have shown that consuming small amounts of vinegar before a meal containing starches may blunt a rise in blood sugar afterward, reducing the glycemic response by 20 to 40 percent, Dr. Johnston said, by partially inhibiting the digestion of starch. 
 
 “The vinegar is taking the starch and making a portion of it fiberlike, so some of the starch will escape digestion,” she explained, adding that test tube studies have shown that the acetic acid in vinegar inhibits enzymes that help in the digestion of starch. 
 
 Dr. Johnston’s own studies have found lower fasting blood glucose concentrations in people who ingested a tablespoon of vinegar. Swedish researchers also reported higher feelings of satiety in those drinking vinegar, though other researchers have attributed this effect to feelings of nausea from drinking the liquid. 
 
 Slowing the rise in blood sugar after a meal could aid weight loss, said Dr. David S. Ludwig, author of the book "Always Hungry?" and a professor of nutrition at the Harvard T.H. Chan School of Public Health. 
 
 “The main problem with the modern diet is that the processed carbohydrates we eat are digested and absorbed too quickly, which leads to a surge in blood sugar and insulin and then a crash a few hours later” that triggers another bout of hunger, Dr. Ludwig said. He advocates eating carbohydrates that are digested more slowly, like beans, fruits, vegetables and whole grains. But he cautioned that vinegar should be used in “doses that have been consumed by humans for centuries, not pharmacological doses,” and called for more studies. 
 
 Straight vinegar can be hard to swallow and may cause you to gasp and aspirate vinegar into the lung, which could potentially lead to pneumonia. Published case reports have linked vinegar consumption to vocal cord spasms, fainting and injury to the esophagus. And Dutch physicians reported on a case of a 15-year-old whose teeth eroded because she had been drinking a glass of apple cider vinegar every day for weight loss. 
 
 When people tell Dr. Johnston they want to try using vinegar to aid weight loss, “I always tell them to dilute it in water, one tablespoon to eight ounces of water, and ingest it with the first bites of the meal. You want the acid to beat the starch into the intestines.” Any kind of vinegar will do, as long as it contains at least 5 percent acetic acid, though she noted that some fancy vinegars contain added sugar, which can increase calorie counts. 
 
 Several dietitians who work with people with diabetes urged caution, however. Consuming vinegar is not part of any of the American Diabetes Association’s nutritional recommendations, said Dr. Margaret Powers, a registered dietitian and diabetes educator and president of health care and education at the association. She said that vinegar should not be considered “a magic bullet” for weight loss or diabetes management. 
 
 Katherine Zeratsky, a registered dietitian and nutritionist at the Mayo Clinic in Rochester, Minn., agreed. “There’s nothing in and of itself wrong with vinegar,” she said. “But if someone who has diabetes thinks, ‘Gosh, if I don’t want to take medicine, I could treat myself with vinegar,’ the recommendation would be: no.” 
 
 Vinegar, applied to the skin, is also often touted as an antidote to nail fungus, head lice and warts, but there is little scientific evidence that these treatments work.
– Drinking vinegar for weight loss? The fad may be appearing all over social media, but it's "as gross as it sounds," and sipping vinegar is not the weight-loss miracle it's purported to be, reports Glamour after talking to dietitians. While drinking vinegar may aid in weight loss, "it is not magic," says one of them, author Beth Warren. Another says drinking vinegar could cause stomach discomfort and acid reflux. (Some researchers think it's those adverse effects that actually curb the appetite.) The recent hubbub about vinegar seems to stem from a 2009 Japanese study, in which obese adults dropped two to four pounds in 12 weeks after taking up to two tablespoons of apple cider vinegar daily. Other outlets echo Glamour's findings. Nutritionist Carol Johnston tells the New York Times that vinegar can help you shed pounds "if you're a very, very patient person," but, she adds in a now-common refrain, it's not a "magic bullet." Vinegar may help, Johnston tells the Washington Post, by inhibiting enzymes that help digest starch. The less starch you digest, the less your blood sugar spikes after eating carbs. Over time, those undigested calories may add up to "very modest" weight loss. To those who want to give vinegar a shot, experts advise ingesting just one tablespoon in eight ounces of water during the first bites of a meal. And Johnston notes, it needn't be apple cider vinegar—red wine vinegar or white vinegar will do. But take with caution: Consumption of vinegar, per the Times, has been linked to vocal cord spasms, fainting, damage to the esophagus, and tooth erosion. (Capsules filled with freeze-dried poop may some day help people lose weight.)