Posted on Mar 15, 2012, 6 a.m.
Among older men and women, the amino acid leucine may help to synthesize muscle.
Leucine is a branched chain amino acid, which is utilized by the body to manufacture proteins and maintain muscle mass. Whereas meat provides leucine, it is recognized that many older people may not consume such protein sources in adequate amounts. Insufficient protein intake may result in sarcopenia, or age-related muscle mass loss. Douglas Paddon-Jones, from the University of Texas (Texas, USA), and colleagues enrolled eight healthy older people, average age 68 years, and supplemented their meals with leucine at a dose of 12 g per day, for 14 days. Finding that that leucine supplementation increased the rate of protein synthesis, as well as markers of nutrients signaling, the study authors conclude that: "leucine supplementation may improve muscle protein synthesis in response to lower protein meals.”
Shanon L. Casperson, Melinda Sheffield-Moore, Susan J. Hewlings, Douglas Paddon-Jones. “Leucine supplementation chronically improves muscle protein synthesis in older adults consuming the RDA for protein.” Clinical Nutrition, 20 February 2012.