Animal protein intake reduces risk of functional impairment and strength loss in older adults.

Pubmed ID: 32753351

Journal: Clinical nutrition (Edinburgh, Scotland)

Publication Date: March 1, 2021

Affiliation: Preventive Medicine and Epidemiology, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA. Electronic address: llmoore@bu.edu.

MeSH Terms: Humans, Male, Female, Aged, Aged, 80 and over, Risk Factors, Middle Aged, Diet, Diet Surveys, Exercise, Geriatric Assessment, Hand Strength, Frail Elderly, Sarcopenia, Frailty, Animal Proteins, Dietary, Functional Status, Muscle Strength Dynamometer, Plant Proteins, Dietary

Grants: N01HC25195, HHSN268201500001I

Authors: Moore LL, Bradlee ML, Singer MR, Mustafa J, Pickering RT, Yuan M

Cite As: Yuan M, Pickering RT, Bradlee ML, Mustafa J, Singer MR, Moore LL. Animal protein intake reduces risk of functional impairment and strength loss in older adults. Clin Nutr 2021 Mar;40(3):919-927. Epub 2020 Jul 15.

Studies:

Abstract

BACKGROUND & AIMS: Protein intake has been shown to lower risk of aging-related functional decline. The goal of this study was to assess long-term effects of weight-adjusted animal (AP) and plant protein (PP) intakes on aging-related change in functional status and grip strength. METHODS: Framingham Offspring Study participants (n = 1896, 891 men and 1005 women), ≥age 50, were followed for an average of 14.4 years. Protein intake derived from two sets of 3-day diet records (exams 3 and 5) was expressed as both weight-adjusted intake (from residuals) and per kilogram of body weight (g/kg/d). Seven tasks from two standardized assessments (Nagi and the Rosow-Breslau scales) were selected to determine functional status at exams 5-9. Functional impairment was defined as failure to complete (or having a lot of difficulty completing) a given task. Grip strength was assessed by dynamometer at exams 7-9. RESULTS: Participants with higher (vs. lower) weight-adjusted intakes of AP and PP maintained higher functional scores (p = 0.001 and p < 0.001, respectively). After accounting for baseline skeletal muscle mass (SMM) and physical activity, only AP was linked with lower risks of functional impairment. Higher AP intake among sedentary individuals led to 29% (95% CI: 0.51-1.00) reduced risks of impairment; among subjects with lower SMM, higher AP was associated with 30% (95% CI: 0.49-0.98) reduced risks. Physical activity and SMM were independently associated with reduced risks of functional impairment, regardless of protein intake. Finally, higher AP intake led to 34% and 48% greater preservation of grip strength in men (p = 0.012) and women (p = 0.034). Results were similar for protein intake expressed as g/kg/d. CONCLUSIONS: Higher AP intake and higher levels of physical activity and SMM were independently associated with lower risks of functional impairment and greater preservation of grip strength in adults over the age of 50 years.