The diets varied in the amount of calories derived from protein. The low-protein diet had 5 percent of calories from protein, the normal-protein diet had 15 percent of calories from protein and the high-protein diet had 25 percent of its calories as protein. All three diets included the same amount of carbohydrates, and fat made up the difference in the calories. All participants were overfed by about 954 calories a day.

 

Everyone gained weight during the overeating period. However, people in the low-protein diet lost 2.2 pounds in muscle mass, while those in the normal- or high-protein groups gained muscle mass during the overeating period. Muscle weighs more than fat, which is why they gained more weight. The excess calories turned to fat among participants who ate a low-protein diet.

 

The make-up of the weight — lean muscle or fat — may be even more important than the number on the scale or body mass index, said Dr. David Heber, director of the Center for Human Nutrition at the University of California, Los Angeles, and co-author of an editorial accompanying the new study. "Calories count," he said. He encourages a high-protein, low-fat diet that is rich in colorful fruits and vegetables. "We are talking about lean protein such as white-meat chicken, ocean fish, turkey, egg whites and certain protein powders. Protein is more satiating, and helps reduce appetite," he explained.

 

Connie Diekman, director of university nutrition at Washington University in St Louis, said: "This study provides support to buy slim vie diet pills the calories-count message as it relates to percent of body fat.