Heart: An American Medical Odyssey Read Online Free PDF Page A

in this country. As we became more affluent and more urbanized, the nation shifted away from a traditional low-fat,agrarian diet and toward a diet high in saturated fats, found mostly in beef, pork, and lamb, as well as associated by-products such as lard, cheese, and cream.
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    On the eve of World War II, the US Army solicited the assistance of a University of Minnesota physiologist to help design a mobile diet for paratroopers. The components of the meal, initially acquired from a Minneapolis grocery store, were hard biscuits, dried sausage, chocolate, and hard candy; they were intended to provide soldiers with thirty-two hundred calories per day in a compact and easy-to-carry package. The final product, which also included Spam, Wrigley’s spearmint gum, and a four-pack of Chesterfield cigarettes, was assembled in a rectangular cardboard container resembling a Cracker Jack box and was called a “K-ration” in honor of its developer, Ancel Keys.
    Following the war, Keys returned to the University of Minnesota interested in deciphering the puzzling increase in US deaths from heart attacks. Despite harsh conditions during World War II, the incidence of heart attacks had dropped significantly in many parts of Europe, but they were on the rise in the United States, where people had been relatively well fed.Beginning in the late 1940s and continuing over the next fifteen years, in what was likely the first-ever prospective cardiac epidemiology study, Keys followed several hundred businessmen from Minneapolis and St. Paul and demonstrated that the higher their cholesterol levels were, the greater their risk was of developing coronary heart disease.
    In the 1950s there remained much uncertainty concerning the interaction between diet and cardiovascular risk, which was reflected in the conclusion of a somewhat ambivalent1957 American Heart Association report:
    The evidence at hand suggest a general association with high rates of consumption of fat, but it is difficult to disentangle this from caloric balance,exercise, changes in body weight, and other metabolic and dietary factors that may be involved. Thus the present evidence does not convey any specific implications for drastic dietary change, specifically in the quantity or type of fat in the diet of the general population, on the premise that such changes will definitely lessen the incidence of coronary artery disease.
    Ancel Keys continued to investigate the interaction between diet and cardiovascular disease and conceived an enormous, international epidemiological project, called the Seven Countries Study, which began in 1958 and has continued for more than fifty years. The study followed nearly thirteen thousand men from the United States, the Netherlands, Finland, Italy, Croatia, Serbia, Greece, and Japan and collected detailed diet and risk factor data such as cholesterol levels and blood pressure. Keys found that meat consumption was high (more than 7 ounces a day) in the United States, Italy, and parts of Yugoslavia and almost nonexistent in Japan. In contrast, fish consumption predominated in Japan but was very low in the United States. The higher the content of dietary saturated fat and the more prevalent meat was in the diet, the higher was the average serum cholesterol level, and the higher was the death rate from heart disease.
    In 1961, the American Heart Association appeared a little more convinced about the role of fat in the genesis of heart disease:
    The reduction or control of fat consumption under medical supervision with reasonable substitution of polyunsaturated for saturated fats is recommended as a possible means of preventing atherosclerosis and decreasing the risk of heart attacks and strokes. . . . More complete information must be obtained before final conclusions can be reached.
    Later that same year, Ancel Keys was profiled in a cover story in Time magazine, titled “The Fat of the Land,” in which he promoted his version of