Study identifies foods that promote weight maintenance
For people who have dieted this year and are trying to maintain a healthful weight, turkey leftovers — without the stuffing — may be a smart strategy going forward, according to a new report. In the largest diet study in Europe to date, foods that were high in protein and low on the glycemic index — such as poultry, eggs, fish and nuts — did the best job of helping people maintain their weight loss for 26 weeks, researchers reported in a recent edition of the New England Journal of Medicine. The diet also was the easiest for study participants to adhere to among the five weight-maintenance diets tested, the study found. Though many people can lose weight, "maintaining weight loss is the difficult part," said study leader Thomas Meinert Larsen, an associate professor of food composition and obesity at the University of Copenhagen. "You have to come up with a diet that is easy to follow and is practical long-term. It's reassuring that the most effective diet in our study seems to be the one that is best maintained."
Larsen and his colleagues assigned 773 adults who had already lost an average of about 24 pounds to one of five healthful diets designed to encourage a stable weight. All of the diets had a moderate fat content — 25 to 30 percent of calories from fat — were low on sugar, high in fiber and had no limits on calories consumed daily. However, the participants were asked to watch their portion sizes and adhere to strict criteria, which varied among the groups, regarding the amount of protein consumed and glycemic index.
The glycemic index (GI) concept was developed in 1981 as a way to rank carbohydrate-containing foods based on their potential to raise blood glucose. Foods classified as “high GI” raise blood glucose more than a food with a “medium GI” or “low GI.” High GI foods range from 70 to 99 and include baked potatoes, watermelon, and graham crackers. Low GI foods have a GI range of 55 or less and include most fruits and vegetables, pasta, legumes, milk, and pumpernickel bread. Medium GI foods, which range between 56 and 69, include foods such as whole wheat products, brown rice, table sugar, sugar confections, regular soda and cheese pizza.
After 26 weeks, those who followed the high-protein, low-glycemic-index diet lost an average of 0.8 pounds. Participants in the other groups gained an average of 0.7 to 3.7 pounds, according to the study. Overall, volunteers who followed a low-protein diet gained an average of 2 pounds more than those who followed a high-protein diet, and those who ate high-glycemic-index foods gained 2 pounds more, on average, than those who ate low-glycemic-index foods.
The study suggests that people feel more satisfied on the high-protein, low-glycemic-index diet and thus will stick with it longer, said researchers.