WEDNESDAY, Feb. 25 (HealthDay News) -- Diets where calories come from a range of fat, protein and carbohydrate combinations are similarly effective in promoting weight loss and reducing cardiovascular risk factors, researchers report in the Feb. 26 issue of the New England Journal of Medicine.
Frank M. Sacks, M.D., from Harvard School of Public Health in Boston, and colleagues randomly assigned 811 overweight adults to one of four diets. The diets consisted of low-fat, average protein (20 percent fat, 15 percent protein, 65 percent carbohydrates), low-fat, high protein (20 percent fat, 25 percent protein, 55 percent carbohydrates), high-fat, average protein (40 percent fat, 15 percent protein, 45 percent carbohydrates), and high-fat, high protein (40 percent fat, 25 percent protein, 35 percent carbohydrates).
After six months, the investigators found that participants lost an average of 6 kilograms, regardless of diet. Although the subjects began to regain weight after a year, weight loss ranged from 2.9 to 3.6 kilograms after two years regardless of fat, protein and carbohydrate content. At the end of the trial, the average weight loss was 4 kilograms, the researchers report. Lipid-related risk factors and fasting insulin levels also improved. Attendance at group instructional sessions strongly predicted weight loss at two years, the authors note.
"In conclusion, diets that are successful in causing weight loss can emphasize a range of fat, protein and carbohydrate compositions that have beneficial effects on risk factors for cardiovascular disease and diabetes," Sacks and colleagues write. "Such diets can also be tailored to individual patients on the basis of their personal and cultural preferences and may therefore have the best chance for long-term success."