Personalized weight loss strategies—the role of macronutrient distribution

Despite the availability of a wide range of different dietary strategies for weight loss, unhealthy weight gain and obesity are growing problems. This Review discusses the efficacy of changes in dietary macronutrient content for healthy weight loss and weight management. The underlying causes of interindividual variations in response to the same dietary approach are also discussed and the feasibility and potential implications of personalized weight loss strategies is considered. A large number of different dietary approaches have been studied in an attempt to achieve healthy, sustainable weight loss among individuals with overweight and obesity. Restriction of energy intake is the primary method of producing a negative energy balance leading to weight loss. However, owing to the different metabolic roles of proteins, carbohydrates and lipids in energy homeostasis, diets of similar overall energy content but with different macronutrient distribution can differentially affect metabolism, appetite and thermogenesis. Evidence increasingly suggests that the fuel values of calories provided by distinct macronutrients should be considered separately, as metabolism of specific molecular components generates differences in energy yield. The causes of variation in individual responses to various diets are currently under debate, and some evidence suggests that differences are associated with specific genotypes. This Review discusses all available systematic reviews and meta-analyses, and summarizes the results of relevant randomized controlled intervention trials assessing the influence of macronutrient composition on weight management. The initial findings of research into personalized nutrition, based on the interactions of macronutrient intake and genetic background and its potential influence on dietary intervention strategies, are also discussed.