The role of diet quality and dietary patterns in predicting muscle mass and function in men over a 15-year period

SUMMARY: A growing body of evidence suggests that diet quality may predict muscle health. This study found that a “Traditional” dietary pattern predicted greater muscle mass, and an anti-inflammatory diet predicted greater muscle mass and better muscle function over 15 years. These findings reinforce the importance of optimising dietary behaviours for healthy ageing. INTRODUCTION: Research investigating the roles of individual nutrients in muscle health fails to account for the synergistic relationships between foods and nutrients. This study aimed to investigate the predictive value of diet quality and dietary patterns for muscle mass and function in men over a 15-year period. METHODS: This longitudinal study was conducted in 522 men from the Geelong Osteoporosis Study with complete dietary and muscle mass or muscle function data at both baseline and 15-year follow-up assessments. Dietary exposures were extracted from food frequency questionnaires and included the Australian Recommended Food Score, the Dietary Inflammatory Index (DII®), and three a posteriori dietary patterns: Plant-focused, Western, and Traditional (Anglo-Australian). Outcome variables included dual-energy X-ray absorptiometry–derived skeletal muscle index (SMI) and muscle function measured with the timed up-and-go (TUG) test. RESULTS: An anti-inflammatory diet and higher scores on a Traditional dietary pattern both predicted greater SMI ((B: −0.04 (95%CI −0.08, −0.00) kg/m(2)) and (B: 0.12 (95%CI 0.04, 0.20) kg/m(2)), respectively), while a pro-inflammatory diet predicted slower TUG (B: 0.11 (95%CI 0.001, 0.21) sec) over the 15-year follow-up period. These associations remained significant following adjustment for confounding variables. There were no associations observed for other dietary exposures. CONCLUSION: A Traditional dietary pattern higher in vegetables, wholegrain cereals, and animal protein was associated with greater skeletal muscle mass, and an anti-inflammatory diet, also rich in vegetables, fruit, and wholegrain cereals, was associated with greater skeletal muscle mass and better muscle function over 15 years. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00198-021-06012-3.