|
January 18, 2026
Higher protein and lower GI diets promote weight maintenance
A large family-based randomized controlled trial found that a higher protein and lower glycemic index (GI) diet significantly improved weight maintenance in adults and body composition in children.1-3 This trial involved families from eight European countries in which at least one overweight parent had lost 8% or more of their initial body weight on an 8 week low calorie diet. Families were then randomly assigned to one of five diets: high-protein-low-GI, high-protein-high-GI, low-protein-low-GI, low-protein-high-GI or a control diet. The diets had no restrictions on energy intake (i.e. ad libitum) to test their ability to regulate appetite and body weight.
After six months, adults assigned to the high-protein-low-GI diet had the lowest weight regain; whereas, the low-protein-high-GI diet was associated with a significant weight regain of 1.67 kg. The isolated effect of the high-protein versus the low-protein diets was 1.44 kg, and the low-GI diet compared to the high-GI diet was 1.09 kg. The percentage of overweight and obese children in the high-protein-low-GI group decreased significantly during the six-month intervention; whereas, the percentage of body fat increased significantly in children in the low-protein-high-GI group compared to those in the other groups.
A total of 548 adults and 465 children completed the trial. Study completion and weight maintenance rates were higher among adults assigned to the high-protein and low-GI diets than among those assigned to the low-protein and high-GI diets. Adults on the high-protein diets were more likely to achieve an additional weight loss of more than 5% of their body weight than those on the low-protein diets. Adults on the low-GI diets were also more likely to achieve an additional weight loss of more than 5% than those on the high-GI diets. In children, the low-protein-high-GI diet increased the percentage of body fat; whereas, the high-protein-low-GI combination was protective against obesity.
For Your Practice
In this large, well-powered, multi-centre randomized controlled trial, a modest increase in protein content and a modest reduction in GI led to a significant improvement in study completion and maintenance of weight loss among adults and helped to protect against obesity in children.¹ At six months, the low-protein groups in this study consumed about 17% of energy as protein, similar to average protein intakes of Canadian adults; whereas the high-protein groups ate about 22% of energy as protein (well within the Acceptable Macronutrient Distribution Range (AMDR) of 10 to 35% of energy from protein). As noted in the accompanying editorial, eating protein may trigger metabolic changes that help people feel fuller than if they ate carbohydrate or fat.² Thus, replacing some of the refined carbohydrates in the diet with protein, such as lean meats, may help people from regaining weight after weight loss.
Want to Learn More?
1. Larsen TM et al. Diets with High or Low Protein Content and Glycemic Index for Weight-Loss Maintenance. N Engl J Med 2010; 363(22):2102-13.
2. Ludwig DS and Ebbeling CB. Weight-Loss Maintenance � Mind over Matter? N Engl J Med 2010; 363(22):2159-61.
3. Papadaki A et al. The Effect of Protein and Glycemic Index on Children's Body Composition: The DiOGenes Randomized Study. Pediatrics 2010; 126(5):e1143-52. Epub.
To learn more about the satiating effect and other health benefits of protein, click here.
|