Monday, May 10, 2021

Guest Review of The Hungry Brain: Outsmarting the Instincts That Make Us Overeat by Stephan J. Guyenet Ph.D.

A correspondent writes in with a review of The Hungry Brain: Outsmarting the Instincts That Make Us Overeat by Stephan J. Guyenet Ph.D.

P.D. Mangan still emphasizes low carb but grudgingly admits Guyenet has the best overall hypothesis.

Guyenet does an excellent job explaining why carbs are not the primary culprit, but rather hyper-palatable junk food. I think there's something to the carb hypothesis, just not sufficient to explain. He cites, for example, hunter gatherer populations who consume 70% of calories from honey, pure sugar, but boring, with no ill effect on body composition. It's food palatability and variety, guided by a Darwinian unregulated food market that identifies flavor combinations that exploit our natural evolved preferences, that causes leptin resistance and thus obesity. I would order the causes in the following order:

1. Hyper-palatable, cheap ubiquitous processed foods of various macronutrient profiles. Fat + carbs to be what seems to be what really shuts down the leptin system.

2. Polyunsaturated fats causing additional systemic inflammation

3. Overconsumption of sugar driven by novel flavor combinations (see #1) driving additional inflammation through fatty liver

4. Hyper-palatability and endogenous opiates of wheat bread in particular

I think between those four causes, the rest of carb consumption lacks further explanatory value. Pasta and rice consumption, for some reason, don't seem to be associated with obesity despite populations that consume a lot of both. Both rice and pasta lack the surface area to give the same hedonic pleasure as wheat bread. Flour vs. rice is like snorting cocaine vs. chewing a coca leaf.


JP said...

I read Guyenet's book when it came out and thought it was useless. It's very heavy on evo-psych--think of the kind of stuff that behavioral economists write, but applied to food instead of money.

IMO, the biggest flaw of his theory is that most "hyper-palatable" foods are also full of food toxins: gluten and WGA, omega-6s, fructose, soy protein, whatever. So palatability is not the real problem.

It's also worth mentioning that Guyenet is 40 but looks like he's 55, with grey hair, a receding hairline, and overall a sickly appearance. This is a guy who's studied nutrition for his entire adult life--whatever he's doing isn't working. I could write more about why I disliked the book, but SG himself is a better refutation of his ideas than any theoretical argument.

Allan Folz said...

What JP said.

Anonymous said...

The advice given by mainstream dietitians is the best. I am married to one. She and I both a lot younger than our age.