The daily recommended dietary allowance (RDA) for protein is 0.8g/ kg/day for both male and female adults. An increase in the protein intake is mainly suggested to improve the muscle growth and performance, but there was no significant improvement found in older adults, finds a new study published in JAMA Internal Medicine.
"It's amazing how little evidence there is around how much protein we need in our diet, especially the value of high-protein intake," said corresponding author Bhasin, director of the Research Program in Men's Health in the Division of Aging and Metabolism at BWH. "Despite a lack of evidence, experts continue to recommend high-protein intake for older men. We wanted to test this rigorously and determine whether protein intake greater than the recommended dietary allowance is beneficial in increasing muscle mass, strength and wellbeing."
The clinical trial, known as the Optimizing Protein Intake in Older Men (OPTIMen) Trial, was a randomized, placebo-controlled, double-blind, parallel group trial in which men aged 65 or older were randomized to receive a diet containing 0.8g/kg/day protein and a placebo injection; 1.3g/kg/day protein and a placebo injection; 0.8g/kg/day protein and a weekly injection of testosterone; or 1.3g/kg/day protein and a weekly injection of testosterone. All participants were given prepackaged meals with individualized protein and energy contents and supplements. Seventy-eight participants completed the six-month trial.
"Our data highlight the need for re-evaluation of the protein recommended daily allowance in older adults, especially those with frailty and chronic disease," the authors concluded.