A scientific review in April's Nutrition Reviews shows that a vegetarian diet is highly effective for weight loss.
Vegetarian populations tend to be slimmer than meat-eaters, and they experience lower rates of heart disease, diabetes, high blood pressure, and other life-threatening conditions linked to overweight and obesity. The new review, compiling data from 87 previous studies, shows the weight-loss effect does not depend on exercise or calorie-counting, and it occurs at a rate of approximately 1 pound per week.
Rates of obesity in the general population are skyrocketing, while in vegetarians, obesity prevalence ranges from 0 percent to 6 percent, note study authors Susan E. Berkow, Ph.D., C.N.S., and Neal D. Barnard, M.D., of the Physicians Committee for Responsible Medicine (PCRM).
The authors found that the body weight of both male and female vegetarians is, on average, 3 percent to 20 percent lower than that of meat-eaters. Vegetarian and vegan diets have also been put to the test in clinical studies, as the review notes. The best of these clinical studies isolated the effects of diet by keeping exercise constant. The researchers found that a low-fat vegan diet leads to weight loss of about 1 pound per week, even without additional exercise or limits on portion sizes, calories, or carbohydrates.
"Our research reveals that people can enjoy unlimited portions of high- fiber foods such as fruits, vegetables, and whole grains to achieve or maintain a healthy body weight without feeling hungry," says Dr. Berkow, the lead author.