Long-term Intake of Vegetables and Fruits and Subjective Cognitive Function in US Men

Objective: To evaluate the prospective association of long-term intake of vegetables and fruits with late-life subjective cognitive function (SCF).

Methods: Among 27,842 men with a mean age of 51 years in 1986, we used multinomial logistic regression to examine the relation of vegetable and fruit consumption to future SCF. Average dietary intake was calculated from 5 repeated food frequency questionnaires collected every 4 years until 2002. SCF score was assessed twice (2008 and 2012) using a 6-item questionnaire; validity was supported by strong associations with ε4 genotype. We categorized the average of the 2 scores as good, moderate, and poor SCF.

Results: Higher intakes of total vegetables, total fruits, and fruit juice were each significantly associated with lower odds of moderate or poor SCF after controlling for major nondietary factors and total energy intake. The association with total fruit intake was weaker after further adjusting for major dietary factors. In this model, the multivariate odds ratios (95% confidence intervals) for vegetable intake (top vs bottom quintile) were 0.83 (0.76-0.92), trend <0.001 for moderate SCF and 0.66 (0.55-0.80), trend <0.001 for poor SCF. For orange juice, compared to <1 serving/mo of intake, daily consumption was associated with a substantially lower odds of poor SCF (0.53 [0.43-0.67], trend <0.001). Higher consumption of vegetables and fruits 18 to 22 years before SCF assessment was associated with lower odds of poor SCF independent of more proximal intake.

Conclusion: Our findings support a long-term beneficial role of vegetable, fruit, and orange juice consumption on SCF.