Over twenty years ago, we evaluated diet, serum cholesterol, and other variables in 1900 middle-aged men and repeated the evaluation one year later. No therapeutic suggestions were made. Vital status was determined at the 20th anniversary of the initial examination. Scores summarizing each participant's dietary intake of cholesterol, saturated fatty acids, and polyunsaturated fatty acids were calculated according to the formulas of Keys and Hegsted and their co-workers. The two scores were highly correlated, and results were similar for both: there was a positive association between diet score and serum cholesterol concentration at the initial examination, a positive association between change in diet score and change in serum cholesterol concentration from the initial to the second examination, and a positive association prospectively between mean base-line diet score and the 19-year risk of death from coronary heart disease. These associations persisted after adjustment for potentially confounding factors. The results support the conclusion that lipid composition of the diet affects serum cholesterol concentration and risk of coronary death in middle-aged American men.

Intake of dietary provitamin A (carotene) was inversely related to the 19-year incidence of lung cancer in a prospective epidemiological study of 1954 middle-aged men. The relative risks of lung cancer in the first (lowest) to fourth quartiles of the distribution of carotene intake were respectively, 7.0, 5.5, 3.0, and 1.0 for all men in the study, and 8.1, 5.6, 3.9, and 1.0 for men who had smoked cigarettes for 30 or more years. Intake of preformed vitamin A (retinol) and intake of other nutrients were not significantly related to the risk of lung cancer. Neither carotene nor retinol intake was significantly related to the risk of other carcinomas grouped together, although for men in whom epidermoid carcinomas of the head and neck subsequently developed, carotene intake tended to be below average. These results support the hypothesis that dietary beta-carotene decreased the risk of lung cancer. However, cigarette smoking also increases the risk of serious diseases other than lung cancer, and there is no evidence that dietary carotenoids affect these other risks in any way.

The relations between coffee consumption and 19-year mortality from all causes, coronary heart disease, and non-coronary causes were assessed in 1,910 white males aged 40-56 years in 1957-1958 from the Chicago Western Electric Company Study. Mortality rates, adjusted for age, serum cholesterol, diastolic blood pressure, and smoking status, were compared for those consuming 0-1, 2-3, 4-5, and 6+ cups of coffee per day; coffee intake, measured at the first anniversary examination, included both caffeinated and decaffeinated intake. Mortality from all causes was greatest in the highest and lowest intake groups. The increased mortality in the 6+ cups per day group was due to coronary heart disease, while the increased mortality in the lowest intake group was due to noncoronary causes. The adjusted relative risk of coronary heart disease death for those drinking 6+ cups of coffee per day compared with those drinking less was 1.71 (95 per cent confidence limits 1.27, 2.30). This increased risk of coronary heart disease death was present in both smokers and nonsmokers, with adjusted relative risks of 1.62 and 2.21, respectively (95 per cent confidence limits 1.17, 2.24 and 1.06, 4.62). The increased mortality from non-coronary causes in the lowest intake group was due primarily to increased mortality from cancer and cardiovascular diseases other than coronary heart disease. The results of this study support the hypothesis that those who drink 6+ cups of coffee per day may be at an increased risk of death from coronary heart disease.