Dietary Diversity and Mild Cognitive Impairment in Middle-Aged and Older Chinese People: A Cross-Sectional Study

The evidence concerning dietary diversity and cognitive function remains insufficient.

To investigate the association of dietary diversity score (DDS) with mild cognitive impairment (MCI) and cognitive performance in different domains.

Data from The Lifestyle and Healthy Aging of Chinese Square Dancer Study was used in this study. DDS was constructed based on the intake frequencies of 9 food groups assessed by a validated food frequency questionnaire. MCI was diagnosed by Petersen's criteria. A neuropsychological test battery was used to assess the performance on cognitive domains, and test scores were standardized to Z scores. Multiple linear regression models and logistic regression models were used to estimate the β and odds ratios and their 95% CIs, respectively.

Among 1,982 participants, the mean (SD) age was 63.37 (5.00) years, 1,778 (89.71%) were women, and 279 (14.08%) had MCI. Compared to the DDS quartile (0, 6], the multivariable-adjusted odds ratios (95% CI) were 0.74 (0.48, 1.15) for DDS quartile (6, 7], 0.65 (0.43, 0.97) for DDS quartile (7, 8], and 0.55 (0.37, 0.84) for DDS quartile (8, 9]. Furthermore, higher DDS was positively associated with better performance of cognitive domains, including global cognitive function (β= 0.20, 95% CI: 0.12, 0.30), episodic memory (β= 0.21, 95% CI: 0.07, 0.35), attention (β= 0.15, 95% CI: 0.03, 0.26), language fluency (β= 0.24, 95% CI: 0.10, 0.38), and executive function (β= - 0.24, 95% CI: - 0.38, - 0.10).

This study indicated that higher DDS was associated with better cognitive function among middle-aged and older Chinese people.