Overview
As China’s aging population grows rapidly, identifying practical strategies to preserve independence in daily living becomes crucial. A recent longitudinal study using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) provides compelling evidence that dietary diversity is associated with a lower risk of disability in activities of daily living (ADL) among adults aged 65 and older. The research highlights that a varied diet, including protein-rich foods, vegetables, and fruits, may help older adults maintain independence longer.
What is Dietary Diversity and Why It Matters
Dietary diversity score (DDS) measures how many different food groups a person consumes over a given period. In this study, DDS was constructed from nine common food groups in the Chinese diet, excluding grain and oil since they are almost universally consumed daily. A higher DDS signals a more varied, and potentially more nutrient-rich, diet. For older adults, a diverse diet is particularly relevant because aging often accompanies muscle loss, inflammation, and chronic diseases that collectively increase the risk of functional decline.
Key Findings from the CLHLS Longitudinal Analysis
Among 17,464 Chinese adults aged 65 and older who were free of ADL disability at baseline, the average follow-up was about 5.25 years. During this period, 10,750 participants developed disability in ADL, defined as difficulty in tasks such as eating, toileting, bathing, dressing, indoor activities, or continence. The study found a clear, dose–response relationship between DDS and ADL disability risk.
- Compared with the lowest DDS group, those in higher quartiles had progressively lower risk: 0.91, 0.87, and 0.87 hazard ratios for the second, third, and fourth quartiles, respectively, after adjusting for a broad range of factors (age, sex, residence, education, income, lifestyle, comorbidities, and more).
- The trend across DDS quartiles was statistically significant, indicating that higher dietary diversity consistently correlated with lower ADL disability risk.
- Specific food groups also contributed to protection. Protein-rich foods (meat, eggs, beans), fresh vegetables, and fruits showed strong inverse associations with ADL disability after adjusting for multiple covariates. In contrast, fish, salted vegetables, garlic, and tea did not show a significant independent effect after correction for multiple testing.
The study’s nonlinear analysis suggested a dose–response curve in which ADL disability risk declined as DDS rose, eventually plateauing with the highest scores. The inflection point indicated the minimum hazard occurred around a DDS of 8, suggesting substantial benefits with higher dietary diversity.
Implications for Policy and Everyday Life
These findings reinforce the value of promoting dietary diversity in public health strategies aimed at older adults. Public health messaging could emphasize incorporating a mix of protein-rich foods, vegetables, and fruits into daily meals. For communities and caregivers, facilitating access to diverse foods and providing resources for meal planning can help preserve independence and reduce healthcare burdens associated with ADL disability.
Although DDS is a useful proxy for overall nutrient adequacy, the study acknowledges limitations, such as the lack of detailed quantitative intake data and energy adjustment. Nonetheless, the observed associations remained robust after controlling for socioeconomic status, lifestyle factors, and multimorbidity, underscoring the potential impact of diet on aging trajectories.
Why This Matters for Older Chinese Adults
China faces a rapid demographic shift toward an older population, with implications for healthcare systems and quality of life. By fostering dietary diversity, policymakers and communities can take a practical step toward reducing the burden of disability in ADL, helping older adults maintain autonomy and participate fully in daily life.
Conclusion
The CLHLS-based evidence positions dietary diversity as a meaningful, actionable target for preventing ADL disability among older adults. Emphasizing protein-rich foods, vegetables, and fruits within a varied diet may help sustain independence as people age, contributing to healthier, more dignified aging in China and beyond.
