Association between the healthy eating index and sarcopenia in Chinese elderly: a cross-sectional study

Background: Sarcopenia, characterized by the loss of muscle mass and strength, is a major health concern among older adults. It increases the risk of disability and mortality. While nutrition is a key factor in preventing sarcopenia, the relationship between diet quality and sarcopenia, especially through the Healthy Eating Index (HEI), remains limited and inconsistent. Methods: We conducted a cross-sectional analysis of data from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) to examine the association between HEI and sarcopenia in adults aged 60 years and older. HEI scores were derived from the consumption frequency of 13 food groups collected through face-to-face interviews. Sarcopenia was assessed using the SARC-F questionnaire. Multivariable logistic regression models were fitted to estimate the association. Result: Among 14,257 Chinese elders, HEI was inversely associated with the prevalence of sarcopenia. A 1-unit increase in HEI corresponded to a 1.2% reduction in the prevalence of sarcopenia (OR = 0.988, 95% CI: 0.979-0.998, P = 0.014). Compared to the elderly in the first quartile of HEI, multivariable-adjusted ORs for those in the second to fourth quartiles were 0.934 (95% CI: 0.796-1.095), 0.839 (95% CI: 0.709-0.992), and 0.772 (95% CI: 0.641-0.930). Subgroup analysis revealed heterogeneous associations across different sub-populations. Restricted cubic spline analysis showed a negative and linear relationship between HEI and sarcopenia in the overall population (P-overall = 0.049, P-nonlinear = 0.971), which remained significant in males, females, and those aged 75 years or older. Conclusion: Better diet quality, reflected by higher HEI scores, is associated with a lower prevalence of sarcopenia in older adults, highlighting the importance of nutrition in preventing sarcopenia.