Overview
New longitudinal evidence from a large Chinese cohort shows that higher dietary diversity is associated with a reduced risk of disability in activities of daily living (ADL) among adults aged 65 and older. This finding adds to the growing body of literature suggesting that diverse, protein-rich and plant-based foods support healthier aging and greater independence in older populations.
What was studied
The study analyzed 17,464 Chinese adults aged ≥65 who did not have ADL disability at baseline, drawing data from the Chinese Longitudinal Healthy Longevity Study (CLHLS). Dietary diversity was measured at baseline using a nine-item food frequency questionnaire, creating a dietary diversity score (DDS) that ranged from 0 to 9. ADL disability was tracked over a mean follow-up of 5.25 years and defined by dependence in activities such as eating, bathing, dressing, toileting, indoor activities, and continence. Participants were grouped into four DDS quartiles.
Key findings
Compared with those in the lowest DDS quartile, higher DDS was linked to a lower risk of developing ADL disability:
- Second quartile: HR 0.91 (95% CI 0.85–0.96)
- Third quartile: HR 0.87 (95% CI 0.82–0.92)
- Fourth quartile: HR 0.87 (95% CI 0.83–0.92)
There was a clear dose-response relationship, with a plateauing effect at very high DDS levels. Notably, consumption of protein-rich foods (meat, eggs, beans) and plant foods (fresh vegetables, fruits) showed protective associations with reduced ADL disability risk.
What foods mattered most
After adjusting for multiple factors, the study found significant associations between DDS-related protection and several foods:
- Meat: reduced risk (HR 0.90, 95% CI 0.86–0.95)
- Eggs: reduced risk (HR 0.93, 95% CI 0.87–0.98)
- Beans: reduced risk (HR 0.94, 95% CI 0.89–0.99)
- Fresh vegetables: reduced risk (HR 0.92, 95% CI 0.89–0.97)
- Fruits: reduced risk (HR 0.88, 95% CI 0.78–0.98)
Other items like fish, salted vegetables, garlic, and tea did not show a statistically significant independent effect after correction.
Implications for public health
With China’s rapidly aging population, strategies that promote healthy aging and independence are crucial. This study suggests that encouraging a diverse diet—particularly with adequate protein sources, vegetables, and fruits—could help delay or prevent disability in ADL. Public health initiatives might focus on nutrition education for older adults and caregivers and ensuring access to a range of nutritious foods in communities and long-term care settings.
Strengths and limitations
The study’s strengths include its large, nationwide, community-dwelling sample and robust adjustment for demographic, lifestyle, and health confounders. DDS was derived from a validated FFQ reflecting long-term intake. Limitations include lack of detailed quantitative intake data (no exact energy-adjusted nutrients), potential residual confounding, and the observational design, which cannot prove causality. Event timing was based on follow-up intervals, which could introduce measurement imprecision for when disability occurred.
Conclusion
A higher dietary diversity score is associated with a lower risk of disability in ADL among older Chinese adults. The protective effect is strongest for protein-rich foods, vegetables, and fruits. Promoting dietary diversity could support healthier aging and greater independence in daily activities.
