In 1977, in one of the more perverse episodes in the history of our ongoing discourse on obesity, a subcommittee of the U.S. Congress held a hearing in which the assembled congressional members listened to the leading academic experts of the day expound on the cause and treatment of obesity and its supposedly vital relationship to calories consumed and expended. 

The testimony left Henry Bellmon, a senator from Oklahoma, scratching his head, perhaps because Bellmon seemed to know what it was like to fatten easily and struggle with his weight. Maybe he was talking about himself. If not, it was surely a loved one who had opened his mind. “I want to be sure we don’t oversimplify,” Bellmon said. 

“… We make it sound like there is no problem for those of us who are overweight except to push back from the table sooner. But I watched Senator [Robert] Dole in the Senate dining room, a double dip of ice cream, a piece of blueberry pie, meat and potatoes, yet he stays as lean as a west Kansas coyote. Some of the rest of us who live on lettuce, cottage cheese and RyKrisp don’t do nearly as well. Is there a difference in individuals as to how they utilize fuel?”

 The experts in attendance acknowledged that they “constantly hear anecdotes of this type,” but they could offer no other words of explanation. Their conviction in the primacy of gluttony didn’t allow it. In fact, the evidence has always been clear, but it can’t be reconciled with the notion that obesity is caused by eating too much and exercising too little. Like Senator Bellmon, those of us who want to achieve and maintain a healthy weight can’t afford to think about obesity as an energy balance problem. It gets us nowhere we haven’t already been our entire lives. We have to think about it as a hormonal, metabolic, and physiological problem, perhaps akin to diabetes, as Astwood suggested. Some of us who don’t seem to have it now are going to get it as we age. Some of us aren’t. Some of us can load up on ice cream, pie, meat, and potatoes and stay lean as a west Kansas coyote; some of us can’t. But the foods we eat strongly influence the hormones responsible, as I’ll discuss. That’s textbook medicine. As such, the ubiquitous and seemingly obvious advice to eat “healthy,” as the authorities invariably define it, is not relevant to all of us. The adverb healthy in that advice is a synonym for eating as the lean and healthy tend to do, but we are not them. We fatten easily; they don’t. Doing as they do might surely be better for us than eating the standard Western fare of processed foods—“foodlike substances,” as Michael Pollan memorably called them—and drinking sugary beverages (sodas, fruit juices, energy drinks, mocha latte cappuccinos) morning to night, but that’s not good enough. It may also do harm or at least continue harm to be done. We have to eat differently because we are different.

Gary Taubes. The Case for Keto: Rethinking Weight Control and the Science and Practice of Low-Carb/High-Fat Eating (Kindle Locations 711-718). Knopf. Kindle Edition.