Low protein intake, physical activity and physical function in European and North American community-dwelling older adults: a pooled analysis of four longitudinal aging cohorts
Nuno Mendonça, Linda M Hengeveld, Marjolein Visser, Nancy Presse, Helena Canhão, Eleanor M Simonsick, Stephen B Kritchevsky, Anne B Newman, Pierrette Gaudreau, Carol Jagger
American Journal of Clinical Nutrition 2021
Dietary protein may slow the decline in muscle mass and function with aging, making it a sensible candidate to slow down or even prevent disability progression. At present, studies providing reliable estimates of the association between protein intake and physical function, and its interaction with physical activity, in community-dwelling older adults are lacking. We wanted to investigate the longitudinal relationship between protein intake and physical function, as well as how the results varied with different physical activity levels. For this we used individual participant data from four cohorts in the PROMISS consortium (Health ABC, NuAge, LASA and Newcastle 85+) with more than 5700 participants living in the community and followed up to almost 9 years. We found that higher daily protein intake may reduce physical function decline not only in older adults with protein intake below the current recommended dietary allowance of 0.8 grams/kg bodyweight/day, but also in those with a protein intake that is already considered sufficient, i.e. above and beyond the 0.8 grams/kg bodyweight/day. This dose-dependent association was observed for all levels of physical activity, suggesting that the results on the association between protein intake and physical function do not change by physical activity level.