Mortality in vegetarians and nonvegetarians: detailed findings from a collaborative analysis of 5 prospective studies

We combined data from 5 prospective studies to compare the death rates from common diseases of vegetarians with those of nonvegetarians with similar l ifestyles. A summary of these results was reported previously; we report he re more details of the findings. Data for 76172 men and women were availabl e. Vegetarians were those who did not eat any meat or fish (n = 27808). Dea th rate ratios at ages 16-89 y were calculated by Poisson regression and al l results were adjusted for age, sex, and smoking status. A random-effects model was used to calculate pooled estimates of effect for all studies comb ined. There were 8330 deaths after a mean of 10.6 y of follow-up. Mortality from ischemic heart disease was 24% lower in vegetarians than in nonvegeta rians (death rate ratio: 0.76; 95% CI: 0.62, 0.94; P < 0.01). The lower mor tality from ischemic heart disease among vegetarians was greater at younger ages and was restricted to those who had followed their current diet for > 5 y. Further categorization of diets showed that, in comparison with regula r meat eaters, mortality from ischemic heart disease was 20% lower in occas ional meat eaters, 34% lower in people who ate fish but not meat, 34% lower in lactoovovegetarians, and 26% lower in vegans. There were no significant differences between vegetarians and nonvegetarians in mortality from cereb rovascular disease, stomach cancer, colorectal cancer, lung cancer, breast cancer, prostate cancer, or all other causes combined.