said. But in November 1966, just nine months later, the Anti-Coronary Club investigators published a second article, revealing that twenty-six members of the club had died during the trial, compared with only six of the men whose diet had not been prudent. Eight members of the club died from heart attacks, but none of the controls. This appeared “somewhat unusual,” Christakis and his col eagues acknowledged.
They discussed the improvements in heart-disease risk factors (cholesterol, weight, and blood pressure decreased) and the significant reduction in debilitating il ness “from new coronary heart disease,” but omitted further discussion of mortality.
This mortality problem was the bane of Keys’s dietary-fat hypothesis, bedeviling every trial that tried to assess the effects of a low-fat diet on death as wel as disease. In July 1969, Seymour Dayton, a professor of medicine at the University of California, Los Angeles, reported the results of the largest diet-heart trial to that date. Dayton gave half of nearly 850 veterans residing at a local Veterans Administration hospital a diet in which corn, soybean, safflower, and cottonseed oils replaced the saturated fats in butter, milk, ice cream, and cheeses. The other half, the controls, were served a placebo diet in which the fat quantity and type hadn’t been changed. The first group saw their cholesterol drop 13 percent lower than the controls; only sixty-six died from heart disease during the study, compared with ninety-six of the vets on the placebo diet.*8
Thirty-one of the men eating Dayton’s experimental cholesterol-lowering diet, however, died of cancer, compared with only seventeen of the controls.
The risk of death was effectively equal on the two diets. “Was it not possible,” Dayton asked, “that a diet high in unsaturated fat…might have noxious effects when consumed over a period of many years? Such diets are, after al , rarities among the self-selected diets of human population groups.”
Because the cholesterol-lowering diet failed to increase longevity, he added, it could not provide a “final answer concerning dietary prevention of heart disease.”
If these trials had demonstrated that people actual y lived longer on cholesterol-lowering diets, there would have been little controversy. But almost four decades later, only one trial, the Helsinki Mental Hospital Study, seemed to demonstrate such a benefit—albeit not from a low-fat diet but from a high-polyunsaturated, low-saturated-fat diet.
The Helsinki Study was a strange and imaginative experiment. The Finnish investigators used two mental hospitals for their trial, dubbed Hospital K
(Kel okoski Hospital) and Hospital N (Nikkilä Hospital). Between 1959 and 1965, the inmates at Hospital N were fed a special cholesterol-lowering diet,†
9 and the inmates of K ate their usual fare; from 1965 to 1971, those in Hospital K ate the special diet and the Hospital N inmates ate the usual fare. The effect of this diet was measured on whoever happened to be in the hospitals during those periods; “in mental hospitals turnover is usual y rather slow,” the Finnish investigators noted.
The diet seemed to reduce heart-disease deaths by half. More important to the acceptance of Keys’s hypothesis, the men in the hospitals lived a little longer on the cholesterol-lowering diet. (The women did not.)
Proponents of Keys’s hypothesis wil stil cite the Helsinki Study as among the definitive evidence that manipulating dietary fats prevents heart disease and saves lives. But if the lower death rates in the Helsinki trial were considered compel ing evidence that the diet worked, why weren’t the higher death rates in the Anti-Coronary Club Trial considered evidence that it did not?
The Minnesota Coronary Survey was, by far, the largest diet-heart trial carried out in the United States, yet it played no role in the evolution of the dietary-fat hypothesis. Indeed, the results of the study went
They discussed the improvements in heart-disease risk factors (cholesterol, weight, and blood pressure decreased) and the significant reduction in debilitating il ness “from new coronary heart disease,” but omitted further discussion of mortality.
This mortality problem was the bane of Keys’s dietary-fat hypothesis, bedeviling every trial that tried to assess the effects of a low-fat diet on death as wel as disease. In July 1969, Seymour Dayton, a professor of medicine at the University of California, Los Angeles, reported the results of the largest diet-heart trial to that date. Dayton gave half of nearly 850 veterans residing at a local Veterans Administration hospital a diet in which corn, soybean, safflower, and cottonseed oils replaced the saturated fats in butter, milk, ice cream, and cheeses. The other half, the controls, were served a placebo diet in which the fat quantity and type hadn’t been changed. The first group saw their cholesterol drop 13 percent lower than the controls; only sixty-six died from heart disease during the study, compared with ninety-six of the vets on the placebo diet.*8
Thirty-one of the men eating Dayton’s experimental cholesterol-lowering diet, however, died of cancer, compared with only seventeen of the controls.
The risk of death was effectively equal on the two diets. “Was it not possible,” Dayton asked, “that a diet high in unsaturated fat…might have noxious effects when consumed over a period of many years? Such diets are, after al , rarities among the self-selected diets of human population groups.”
Because the cholesterol-lowering diet failed to increase longevity, he added, it could not provide a “final answer concerning dietary prevention of heart disease.”
If these trials had demonstrated that people actual y lived longer on cholesterol-lowering diets, there would have been little controversy. But almost four decades later, only one trial, the Helsinki Mental Hospital Study, seemed to demonstrate such a benefit—albeit not from a low-fat diet but from a high-polyunsaturated, low-saturated-fat diet.
The Helsinki Study was a strange and imaginative experiment. The Finnish investigators used two mental hospitals for their trial, dubbed Hospital K
(Kel okoski Hospital) and Hospital N (Nikkilä Hospital). Between 1959 and 1965, the inmates at Hospital N were fed a special cholesterol-lowering diet,†
9 and the inmates of K ate their usual fare; from 1965 to 1971, those in Hospital K ate the special diet and the Hospital N inmates ate the usual fare. The effect of this diet was measured on whoever happened to be in the hospitals during those periods; “in mental hospitals turnover is usual y rather slow,” the Finnish investigators noted.
The diet seemed to reduce heart-disease deaths by half. More important to the acceptance of Keys’s hypothesis, the men in the hospitals lived a little longer on the cholesterol-lowering diet. (The women did not.)
Proponents of Keys’s hypothesis wil stil cite the Helsinki Study as among the definitive evidence that manipulating dietary fats prevents heart disease and saves lives. But if the lower death rates in the Helsinki trial were considered compel ing evidence that the diet worked, why weren’t the higher death rates in the Anti-Coronary Club Trial considered evidence that it did not?
The Minnesota Coronary Survey was, by far, the largest diet-heart trial carried out in the United States, yet it played no role in the evolution of the dietary-fat hypothesis. Indeed, the results of the study went
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