Protein metabolic roles in treatment of obesity

Purpose of review To understand the potential benefits of increased dietary protein during weight loss and the importance of distribution of high-quality protein at each meal. Recent findings Popular weight loss diets emphasize use of protein as a substitute for carbohydrates or fat to reduce insulin and minimize hunger and food cravings. These diets produce short-term weight loss, but long-term benefits remain obscured by failure to differentiate between outcomes of subject compliance and diet effectiveness. New molecular mechanisms have defined the benefits of protein as a meal threshold for the branched-chain amino acid leucine, which has been characterized as a unique signal regulator of muscle protein synthesis. Leucine consumed at 2.5 g triggers a postmeal anabolic response that protects metabolic active tissues during weight loss and increases loss of body fat. Summary Balanced daily distribution of protein with increased intake at breakfast and lunch protects metabolically active tissues including skeletal muscle during weight loss.