One of the most promising nutritional supplements for the preservation of muscle mass in old age is beta-hydroxy-beta-methylbutyrate (HMB), for preserving lean body mass in muscle wasting conditions.It is said that Daily HMB supplementation (typically up to 3 g/day) is demonstrated to have an anti-catabolic effect, enhance protein synthesis, attenuate proteolysis, increase muscle mass, and decrease muscle damage in older adults.This seems like a good source of HMB.