In the journals
Can higher protein intake build more muscle in older men? Not according to a study in the April 2018 JAMA Internal Medicine.
The researchers randomized 92 men, average age 73, into four groups. One group followed a daily diet containing 0.8 grams (g) of protein per kilogram (kg) of body weight, the daily Recommended Dietary Allowance (RDA) for all adults, and a weekly placebo injection; another consumed 1.3 g/kg and the placebo injection; a third consumed the 0.8-g/kg diet, but also received a weekly 100-mg injection of testosterone, and the fourth group ate a 1.3-g/kg diet and got a weekly testosterone injection. (The testosterone was included to see if higher protein increased the hormone's muscle-growing effect.)
After six months, the researchers found the higher-protein diet made no significant difference in lean body mass, muscle performance, or physical function as measured by exercises like chest presses, six-minute walking distances, and stair-climbing power. The researchers noted the findings don't exclude a potential role for slightly higher protein intake for some men, but that the RDA is not one-size-fits-all, and may need to be re-evaluated based on age and sex.
Image: © Ocskaymark | GettyImages
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.