Data was collected between 2002 and 2007 from 71,751 Seventh-Day Adventist men and women, with an average age of 59. Researchers found that average BMI was lowest among vegans, while average BMI was highest among the meat-eaters. Looking at obesity (defined as having a BMI over 30), researchers found that vegans had the lowest percentage of people who were obese, only 9.4%. While meat-eaters had the highest percentage of people who were obese , 33.3%. About 24 percent of semi-vegetarians were obese, 17.9% of pesco-vegetarians were obese, and 16.7% of lacto-ovo vegetarians were obese.
Even though calorie intake was similar across all the groups, there were differences in the types of nutrients consumed. Meat-eaters had the lowest intake of plant proteins, beta carotene, fiber and magnesium, and the highest intake of heart disease-linked fatty acids.