There is no shortage of diets that will help you take weight off. But to have a lasting effect on your metabolism, you need a lifestyle change. Vegetarianism produces such a change, a new study has found, by reducing muscle fat. In so doing, it was found to be nearly twice as effective at reducing body fat than a conventional anti-diabetic diet. What's more, shedding muscle fat improves glucose and lipid metabolism, which makes vegetarianism even more effective against diabetes than the so-called anti-diabetic diet.

In the study, 74 subjects with type 2 diabetes were randomly assigned to follow either a vegetarian diet or a conventional anti-diabetic diet. The latter adhered to the guidelines prescribed by the European Association for the Study of Diabetes. The vegetarian diet consisted of legumes, grains, fruits, nuts and vegetables, with animal products limited to a maximum of one portion of low-fat yogurt per day.

The scientists tracked fat-storage tissue in the test subjects' thighs using magnetic resonance imaging. They learned that, whereas both diets caused a similar reduction in subcutaneous fat, subfascial fat (the fat found on the surface of muscles) was only reduced in response to the vegetarian diet, and intramuscular fat (the fat found inside of muscles) was more greatly reduced by the vegetarian diet.

Why does this matter? Higher levels of subfascial fat in those suffering from type 2 diabetes has been associated with insulin resistance. By reducing it, a vegetarian diet could have a beneficial effect on glucose metabolism. Lower intramuscular fat could help improve muscular strength and mobility – issues for older people with diabetes.

"Vegetarian diets proved to be the most effective diets for weight loss. However, we also showed that a vegetarian diet is much more effective at reducing muscle fat, thus improving metabolism. This finding is important for people who are trying to lose weight, including those suffering from metabolic syndrome and/or type 2 diabetes. But it is also relevant to anyone who takes their weight management seriously and wants to stay lean and healthy," said lead author, Dr. Hana Kahleová.

The research has been published in the Journal of the American College of Nutrition.