Food Source-Specific Associations Between Dietary Magnesium and Sarcopenia in Chinese Older Adults

Objectives: To examine the cross-sectional and prospective associations of dietary magnesium (Mg), including different food sources, with sarcopenia and its components in older adults. The study used data from the Mr. OS and Ms. OS cohorts, which recruited 4000 community-dwelling older adults in Hong Kong. A total of 3142 participants with complete data at baseline and the 4-year follow-up were included in the analysis. Methods: Dietary intake was evaluated using a validated food frequency questionnaire, and Mg intake was classified into quartiles (Q1–Q4). Sarcopenic status was assessed at baseline and 4-year follow-up. Multivariable logistic and linear regression models were used to examine the associations between Mg (both total and by food source) and sarcopenia and its components, with analyses stratified by sex and adjusted for covariates such as dietary energy, protein intake, sociodemographic factors, lifestyle habits, and medical history. Results: Higher Mg intake was associated with better physical performance. In men, moderate Mg intake was associated with lower odds of incident sarcopenia at 4 years (Q2: OR = 0.57, 95% CI: 0.33–0.97). Mg from fruits and legumes was associated with better physical function and a lower risk of sarcopenia, whereas animal-derived Mg sources, such as poultry, exhibited inconsistent associations. In the prospective analysis, egg-derived Mg was associated with lower sarcopenia odds only in Q3 (OR = 0.63, 95% CI: 0.42–0.95), with this association observed in men but not women. Conclusions and Implications: Higher dietary Mg intake, particularly from plant-based foods, was more consistently associated with better physical function than with sarcopenia risk in older adults. These findings support the role of Mg-rich foods in healthy aging.