After reviewing 12 diet trials, Taiwan researchers have learned that people following a vegetarian diet see better results than dieters on other weight-reducing plans. This was especially true for those that follow a vegan diet that includes no animal products whatsoever.
The study published in the Journal of General Internal Medicine was the first to combine the findings from various independent projects that weighed the results of vegetarian diets against other eating plans, including the Atkins diet and those recommended by the American Diabetes Association and the U.S. National Cholesterol Education Program.
The review included 12 randomized controlled trials that involved 1,151 dieters. The dieters followed a specific eating regime for between nine and 74 weeks.
- Individuals assigned to the vegetarian diet groups lost significantly more weight (around 2.02 kilograms) than dieters who ate meat and other animal products.
- Vegetarians who followed a vegan diet lost even more weight. Comparatively, they lost around 2.52 kilograms more than non-vegetarian dieters.
- Vegetarians who do consume dairy products and eggs lost around 1.48 kilograms more than those on a non-vegetarian diet.
- People following vegetarian diets that prescribe a lower than normal intake of calories - so-called energy restriction - also shed more kilograms than those without any such limitations being placed on their eating habits.
"Vegetarian diets are more effective than non-vegetarian diets for weight loss," says Ru-Yi Huang of E-Da Hospital in Taiwan. Longer-term intervention trials are needed to investigate the effect of vegetarian diets on weight control and cardio-metabolic risk. The abundant intake of whole grains, fruits and vegetables might play a role in the favorable results seen in vegetarian diets.
Huang also said that whole-grain products and vegetables generally have low glycemic index values and don't cause blood sugar levels to spike. Fruits are rich in fiber, antioxidants, minerals and protective chemicals that naturally occur in plants. Whole-grain products contain soluble fiber. Such so-called good fiber helps to delay the speed by which food leaves the stomach and ensures good digestion. It also allows enough nutrients to be absorbed while food moves through the intestines.