Good Calories, Bad Calories

Throughout this period, Van Itallie’s reviews of dietary therapy for obesity were singularly dedicated to dismissing any evidence that favored the use of carbohydrate-restricted diets. They would invariably begin with the declaration that carbohydrate-restricted diets were just another way to restrict calories, and they would proceed to refute claims made about the diets on the basis that these claims (not to be confused with observations of the diets’ efficacy) had not been established beyond reasonable doubt. By the end of these reviews, Van Itallie would promote the continued treatment of obesity by balanced, calorie-restricted diets, while acknowledging that there was “increasing recognition of [their] ineffectiveness.”^*126 He would reject any suggestion that carbohydrate-restricted diets should be tried instead, while simultaneously acknowledging that these diets were “quite popular and have been followed with varying degrees of success by many dieters.”

George Bray’s influence in removing the fattening carbohydrate and carbohydrate-restricted diets from the nutritional wisdom was more subtle than Van Itallie’s, but may have been ultimately more significant. Bray was a graduate of Harvard Medical School. In the late 1960s, he studied animal models of obesity at UCLA’s Harbor General Hospital in Torrance, California. He also collaborated peripherally with Ethan Sims on his experimental obesity studies (Bray had been a medical-school classmate of Sims’s colleague Ed Horton) and had notable disagreements with Sims about how this research should be interpreted. In 1973, Bray cochaired the NIH’s first obesity conference; he then edited and drafted the subsequent NIH report, Obesity in Perspective. In 1977, he chaired the Second International Congress on Obesity and a second NIH conference on obesity. He then edited the NIH report Obesity in America, which was published in 1979. Meanwhile, he edited or wrote three of the half-dozen textbooks or clinical manuals on obesity that were published in the United States during the decade—Treatment and Management of Obesity (1974), The Obese Patient (1976), and Obesity: Comparative Methods of Weight Control (1980)—which means effectively all of those not edited or written by Stunkard.^†127

Bray believed that all diets worked by restricting calories, and since restricting calories eventually failed, nothing else need be discussed. He dismissed as irrelevant the work of those investigators who did actively study the dietary treatment of obesity, like Charlotte Young, who gave the presentation on dietary therapy at the NIH conference on obesity that Bray organized and chaired in 1973. Young specialized in the study of body composition, and she had been studying diets and obesity at Cornell since 1950. In the official NIH report on the conference, Obesity in Perspective. Bray treated her discussion of carbohydrate-restricted diets as naïve and of no consequence. In the book he coedited the year after the conference, Treatment and Management of Obesity, Young’s observations on carbohydrate-restricted diets are described as still requiring further “confirmation before they can be fully accepted…. The question of the value of a low carbohydrate diet and its effectiveness in weight loss is still unresolved.” In The Obese Patient, published three years after the NIH conference, Bray wrote of Young’s studies, “The data are suggestive and require careful replication with larger groups of individuals.” Yet nowhere in the NIH report on the conference, including a lengthy list of research priorities and “gaps in our current knowledge,” did Bray raise the possibility that further research was needed on any dietary therapy for obesity, let alone, as Bray’s own textbooks had suggested, the unresolved question of the value of carbohydrate restriction. Bray then proceeded to become the leading proponent of the hypothesis that obesity, like heart disease, was caused primarily by the dense calories of dietary fat, and thus could be cured or prevented by replacing the fat in the diet with carbohydrates.