Year-long changes in protein metabolism in elderly men and women supplemented with a nutrition cocktail of beta-hydroxy-beta-methylbutyrate (HMB), L-arginine, and L-lysine

JPEN J Parenter Enteral Nutr. 2009 Jan-Feb;33(1):71-82. doi: 10.1177/0148607108322403.


Background: A major contributing factor to the loss of mobility in elderly people is the gradual and continuous loss of lean body mass.

Objectives: To determine whether supplementation of an amino acid cocktail daily for 1 year could improve the age-associated changes in protein turnover and lean body mass in elderly people.

Design: Elderly (76+/-1.6 years) women (n=39) and men (n=38) were recruited for a double-blinded controlled study. Study participants were randomly assigned to either an isonitrogenous control-supplement (n=37) or a treatment-supplement (HMB/Arg/Lys) consisting of beta-hydroxy-beta-methylbutyrate, L-arginine, and L-lysine (n=40) for the 1-year study. Lean tissue mass was measured using both bioelectrical-impedance analysis (BIA) and dual energy x-ray absorptiometry (DXA). Rates of whole-body protein turnover were estimated using primed/intermittent oral doses of 15N-glycine.

Results: In subjects taking the HMB/Arg/Lys supplement, lean tissue increased over the year of study while in the control group, lean tissue did not change. Compared with control, HMB/Arg/Lys increased body cell mass (BIA) by 1.6% (P=.002) and lean mass (DXA) by 1.2% (P=.05). The rates of protein turnover were significantly increased 8% and 12% in the HMB/Arg/Lys-supplemented group while rates of protein turnover decreased 11% and 9% in the control-supplemented subjects (P<.01), at 3 and 12 months, respectively.

Conclusions: Consumption of a simple amino acid-related cocktail increased protein turnover and lean tissue in elderly individuals in a year-long study.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging / physiology
  • Arginine / adverse effects
  • Arginine / therapeutic use*
  • Body Composition / drug effects*
  • Dietary Supplements / adverse effects
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Humans
  • Lysine / adverse effects
  • Lysine / therapeutic use*
  • Male
  • Muscle, Skeletal / drug effects*
  • Muscle, Skeletal / metabolism
  • Patient Compliance
  • Proteins / metabolism*
  • Surveys and Questionnaires
  • Valerates / adverse effects
  • Valerates / therapeutic use*


  • Proteins
  • Valerates
  • beta-hydroxyisovaleric acid
  • Arginine
  • Lysine