Other factors were also pushing the public toward a belief in the evils of dietary fat and cholesterol that the medical-research community itself still considered questionable. The American Heart Association revised its dietary recommendations every two to three years and, with each revision, made its advice to eat less fat increasingly unconditional. By 1970, this prescription applied not just to those high-risk men who had already had heart attacks or had high cholesterol or smoked, but to everyone, “including infants, children, adolescents, pregnant and lactating women, and older persons.” Meanwhile, the press and the public came to view the AHA as the primary source of expert information on the issue.
The AHA had an important ally in the vegetable-oil and margarine manufacturers. As early as 1957, the year Americans first purchased more margarine than butter, Mazola corn oil was being pitched to the public with a “Listen to Your Heart” campaign; the polyunsaturated fats of corn oil would lower cholesterol and so prevent heart attacks, it was said. Corn Products Company, the makers of Mazola, and Standard Brands, producers of Fleischmann’s margarine, both initiated programs to educate doctors to the benefits of polyunsaturated fats, with the implicit assumption that the physicians would pass the news on to their patients. Corn Products Company collaborated directly with the AHA on releasing a “risk handbook” for physicians, and with Pocket Books to publish the revised version, in 1966, of Jeremiah Stamler’s book
This alliance between the AHA and the makers of vegetable oils and margarines dissolved in the early 1970s, with reports suggesting that polyunsaturated fats can cause cancer in laboratory animals. This was problematic to Keys’s hypothesis, because the studies that had given some indication that cholesterol-lowering was good for the heart—Seymour Dayton’s VA Hospital trial and the Helsinki Mental Hospital Study—had done so precisely by replacing saturated fats in the diet with polyunsaturated fats. Public-health authorities concerned with our cholesterol dealt with the problem by advising that we simply eat less fat and less saturated fat, even though only two studies had ever tested the effect of such low-fat diets on heart disease, and they had been contradictory.
It’s possible to point to a single day when the controversy was shifted irrevocably in favor of Keys’s hypothesis—Friday, January 14, 1977, when Senator George McGovern announced the publication of the first
This was the first time that any government institution (as opposed to private groups like the AHA) had told Americans they could improve their health by eating less fat. In so doing,
The document was the product of McGovern’s Senate Select Committee on Nutrition and Human Needs, a bipartisan nonlegislative committee that had been formed in 1968 with a mandate to wipe out malnutrition in America. Over the next five years, McGovern and his colleagues—among them, many of the most prominent politicians in the country, including Ted Kennedy, Charles Percy, Bob Dole, and Hubert Humphrey—instituted a series of landmark federal food-assistance programs. Buoyed by their success fighting malnutrition, the committee members turned to the link between diet and chronic disease.
The operative force at work, however, was the committee staff, composed of lawyers and ex-journalists. “We really were totally naive,” said the staff director Marshall Matz, “a bunch of kids, who just thought, Hell, we should say something on this subject before we go out of business.”*13 McGovern had attended Nathan Pritikin’s four-week diet-and-exercise program at Pritikin’s Longevity Research Institute in Santa Barbara, California. He said that he lasted only a few days on Pritikin’s very low-fat diet, but that Pritikin’s philosophy, an extreme version of the AHA’s, had profoundly influenced his thinking.
McGovern’s staff were virtually unaware of the existence of any scientific controversy. They knew that the AHA advocated low-fat diets, and that the dairy, meat, and egg industries had been fighting back. Matz and his fellow staff members described their level of familiarity with the subject as that of interested laymen who read the newspapers. They believed that the relevant nutritional and social issues were simple and obvious. Moreover, they wanted to make a difference, none more so than Nick Mottern, who would draft the
In July 1976, McGovern’s committee listened to two days of testimony on “Diet and Killer Diseases.” Mottern then spent three months researching the subject and two months writing. The most compelling evidence, Mottern believed, was the changing-American-diet story, and this became the underlying foundation of the committee’s recommendations: we should readjust our national diet to match that of the turn of the century, at least as the Department of Agriculture had guessed it to be. The less controversial recommendations of the
Fat and cholesterol would be the contentious points. Here Mottern avoided the inherent ambiguities of the evidence by relying for his expertise almost exclusively on a single Harvard nutritionist, Mark Hegsted, who by his own admission was an extremist on the dietary-fat issue. Hegsted had studied the effect of fat on cholesterol levels in the early 1960s, first with animals and then, like Keys, with schizophrenic patients at a mental hospital. Hegsted had come to believe unconditionally that eating less fat would prevent heart disease, although he was aware that this conviction was not shared by other investigators working in the field. With Hegsted as his guide, Mottern perceived the dietary-fat controversy as analogous to the specious industry-sponsored “controversy” over cigarettes and lung cancer, and he equated his
Though the
