To clarify the association of dietary diversity and dietary intake frequency with frailty among older adults, and to provide an evidence-based foundation for developing nutritional intervention strategies for frailty prevention and treatment.

Basic information, dietary status, and frailty prevalence (assessed using the frailty index) were collected from 9785 older adults in the 2018 Chinese Longitudinal Healthy Longevity Survey-Home Follow-up (CLHLS-HF). All the participants were divided into the frail group and the non-frail group. T test or χ² test was used to compare the differences in dietary intake between the two groups. Logistic regression was used to analyze the relationship between the intake frequency of 9 routinely monitored food types and frailty in older adults.

The average age of the participants was (85.04±11.52) years, the frailty index was (0.17±0.13), the detection rate of frailty was 24.24% (2 372 cases), and the dietary diversity score was (4.65±1.98) points. Multivariate logistic regression indicated that insufficient dietary diversity (OR=1.239, 95%CI: 1.130-1.359, P < 0.01) was a risk factor for frailty. Conversely, increased intake of fresh vegetables, meat, soy productsand tea could reduce the risk of frailty (OR=0.564, 0.814, 0.847, 0.853; 95%CI: 0.480-0.663, 0.710-0.933, 0.754-0.953, 0.729-0.998, P < 0.05 or P < 0.01).

Insufficient dietary diversity is a risk factor for frailty. Maintaining good dietary diversity, such as increasing the intake of fresh vegetables, meat, soy products, and tea, represents a potential nutritional intervention direction for reducing the risk of frailty in older adults.