Friday, February 27th, 2009

Are All Calories Created Equal?

photo by Flickr user rizkapb.

New research weighs in on the efficacy of several popular weight loss diets, and finds that it's not so much what you eat, but how much of it. Writing in the New England Journal of Medicine, researchers report that a heart-healthy diet that reduces calorie intake can help overweight and obese adults achieve and maintain weight loss -- no matter what the proportions of fat, protein, or carbohydrate in the diet are.

Participants in the study were assigned to follow a diet that was either Low-fat, average protein (20 percent fat, 15 percent protein, 65 percent carbohydrate), low-fat, high protein (20 percent fat, 25 percent protein, 55 percent carbohydrate), high-fat, average protein (40 percent fat, 15 percent protein, 45 percent carbohydrate) or high-fat, high-protein (40 percent fat, 25 percent protein, 35 percent carbohydrate). In each case, however, the number of calories consumed was lower than the total energy requirements for their activity level. "This new information should focus weight loss approaches on reducing calorie intake rather than any particular proportions of fat, protein or carbohydrate," said Frank Sacks, one of the researchers on the study. We'll find out more.