Critiquing Gary Taubes, Part 1: Mainstream Nutrition Science on Obesity

Re­lated: Trust­ing Ex­pert Consensus

Lately, I’ve been think­ing a lot about whether we can find any clear ex­cep­tions to the gen­eral “trust the ex­perts (when they agree)” heuris­tic. One ex­am­ple that keeps com­ing up—at least on LessWrong and re­lated blogs—is Gary Taubes’ claims about main­stream nu­tri­tion ex­perts allegedly get­ting obe­sity hor­ribly wrong.

Taubes is prob­a­bly best-known for his book Good Calories, Bad Calories. I’d pre­vi­ously had a mildly nega­tive im­pres­sion of him from dis­cus­sion of him on Yvain’s old blog, par­tic­u­larly some of other posts Yvain and other peo­ple linked from there, such as this dis­cus­sion of Taubes’ “car­bo­hy­drate hy­poth­e­sis” and es­pe­cially this dis­cus­sion of Taubes’ at­tempt to re­fute the stan­dard calories-in/​calories-out model of weight.

But I figured maybe the crit­i­cism of Taubes I’d read hadn’t been fair to him, so I de­cided to read him for my­self… and holy crap, Taubes turned out to be far worse than I ex­pected. I de­cided to write a post ex­plain­ing why, and then re­al­ized that, even if I were some­what se­lec­tive about the is­sues I fo­cused on, I had enough ma­te­rial for a whole se­ries of posts, which I’ll be post­ing over the course of the next week.

The prob­lem with Taubes is not that ev­ery­thing he says is wrong. Much of it is lu­dicrously wrong, but that’s only one half of the prob­lem. The other half is that he says a fair num­ber of things main­stream nu­tri­tion sci­ence would agree with, but then hides this fact, and in­stead pre­tends those things are a re­fu­ta­tion of main­stream nu­tri­tion sci­ence. So it’s worth start­ing with a brief in-a-nut­shell ver­sion of what main­stream nu­tri­tion sci­ence ac­tu­ally says about obe­sity.

(The fol­low­ing sum­mary is drawn from a num­ber of sources, in­clud­ing this, this, and this. Every­thing I’m about to say will be dis­cussed in much greater de­tail in sub­se­quent posts.)

Here it goes: peo­ple gain weight when they con­sume more calories than they burn. But both calorie in­take and calorie ex­pen­di­ture are reg­u­lated by com­pli­cated mechanisms we don’t fully un­der­stand yet. This means the causes of over­weight and obe­sity* are also com­pli­cated and not fully un­der­stood. It is, how­ever, worth watch­ing out for foods with lots of added fat and sugar, if only be­cause they’re an easy way to con­sume way too many calories.

We cur­rently don’t have any great solu­tions to the prob­lem of over­weight and obe­sity. If you con­sume fewer calories than you burn, you will lose weight, but stick­ing to a diet is hard. It’s rel­a­tively easy to lose weight in the short run, and it’s pos­si­ble to do so on a wide va­ri­ety of diets, but only a small per­centage of peo­ple keep the weight off over the long run.

As for low-carb diets, peo­ple do lose weight on them, but they do so be­cause low-carb diets gen­er­ally lead peo­ple to re­strict their calorie in­take even when they aren’t ac­tively count­ing calories. For one thing, it’s hard to con­sume as many calories when you dras­ti­cally re­strict the range of foods you can eat. There’s also some ev­i­dence that low-carb diets may have some ad­van­tages. in terms of, say, ward­ing off hunger, but the ev­i­dence is mixed. There’s cer­tainly no ba­sis for claiming low-carb diets as a magic bul­let for the prob­lems of over­weight and obe­sity.

The above points are not the only is­sues at stake in Taubes’ writ­ings on nu­tri­tion. Ad­mit­tedly, he cov­ers a huge amount of ground, from the re­la­tion­ship be­tween sugar and di­a­betes to the re­la­tion­ship be­tween fat in­take and heart dis­ease to the alleged dan­gers of ex­tremely-low car­bo­hy­drate diets. How­ever, I’ll be fo­cus­ing on his claims about the causes of and solu­tions to the prob­lems of over­weight and obe­sity, be­cause that seems to be the main thing peo­ple talk about when they talk about Taubes sup­pos­edly show­ing how wrong main­stream ex­perts can be.

I’ll also fo­cus heav­ily on how Taubes mis­rep­re­sents the views of main­stream ex­perts on obe­sity. In the next post, though, I’ll be tem­porar­ily set­ting that is­sue aside in or­der to look at what Taubes is propos­ing as an al­ter­na­tive. This will in­volve ex­am­in­ing some claims made by Dr. Robert Atk­ins, whose ideas’ Taubes cham­pi­ons.

*Note: if the use of “over­weight” as a noun sounds weird to you, it does to me too, but I dis­cov­ered as I re­searched this ar­ti­cle that it’s stan­dard us­age in the liter­a­ture on the sub­ject. I came to re­al­ize there’s a good rea­son for this us­age: it’s in­ac­cu­rate to talk about the prob­lem solely in terms of “obe­sity,” but con­stantly say­ing “the prob­lem of peo­ple be­ing over­weight and obese” gets re­ally wordy.

Next: Atk­ins Redux