WASHINGTON--Vegetarians weigh less than non-vegetarians, independent of food intake or exercise, according to a review conducted by members of the Physician's Committee for Responsible Medicine (PCRM) and slated for publication in the April issue of Nutrition Reviews.
Susan Berkow, Ph.D., and Neal Barnard, M.D., conducted a Medline search for literature containing information on vegetarians and their weight status and found data from of 87 observational studies and randomized controlled trials suggests vegetarian populations have lower body weights and body mass indices (BMIs) than meat-eaters, and experience lower rates of heart disease, diabetes, high blood pressure, and conditions linked to overweight and obesity. The authors noted average body weight of vegetarians is 3-percent to 20-percent lower than that of meat-eaters, without increased exercise or restrictions 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," said Berkow.
According to Barnard, the mechanism behind these effects may involve the way the body metabolizes plant foods. "There is evidence that a vegan diet causes an increased calorie burn after meals, meaning plant-based foods are being used more efficiently as fuel for the body, as opposed to being stored as fat," he said.