Muscle atrophy occurs under a number of different conditions, including disuse and aging accompanied by the onset of sarcopenia. Although muscle mass is reduced by decreased protein synthesis and/or increased protein degradation, the mechanisms of disuse muscle atrophy and sarcopenia differ. Therefore, nutrition strategies need to be customized for each type of muscle atrophy. Difficulties are associated with assessing the efficacy of nutrients for preventing sarcopenia due to uncontrolled factors in human studies. We herein (a) summarize nutritional epidemiology evidence related to sarcopenia from recent systematic reviews, (b) review nutrient supplementation for attenuating sarcopenia through dietary control, and (c) provide evidence for the efficacy of nutrient supplementation for treating disuse muscle atrophy under dietary control. Epidemiological studies have indicated that diets with a sufficient intake of beneficial foods are useful for preventing sarcopenia. Supplementation with vitamin D and leucine-enriched whey protein have been suggested to help attenuate sarcopenia in geriatric patients, particularly those who are unable to exercise. Further studies are needed to clarify the effects of protein and amino acid supplementation on muscle mass and strength. High-quality studies with controlled diets and physical activities are required to clarify the effects of nutritional interventions on both types of muscle atrophy.
Part of the book: Background and Management of Muscular Atrophy