Association between vegetable, fruit, and flavonoid-rich fruit consumption in midlife and major depressive disorder in later life: the JPHC Saku Mental Health Study

We evaluated the association between vegetable and fruit consumption – particularly flavonoid-rich fruits – in mid-life and major depressive disorder (MDD) in later life. We also evaluated the association of nutrients in fruits and vegetables with MDD. Vegetable and fruit consumption and nutrient intake for 1204 individuals were averaged from data obtained in 1995 and 2000. MDD was diagnosed by certified psychiatrists in 2014–2015. Logistic regression was used to examine the odds of MDD according to quintile of vegetable and fruit consumption and quartile of nutrient intake. We fitted two regression models, using hierarchical adjustment for age, sex, employment status, alcohol consumption, current smoking, and physical activity. Bias-corrected and accelerated bootstrap confidence intervals were used to obtain accurate information. In fully adjusted models, the highest quintile of total fruit consumption excluding juice and flavonoid-rich fruit consumption showed decreased odds of MDD compared with the lowest quintile (OR = 0.34, 95% CI = 0.15–0.77; OR = 0.44, 95% CI = 0.20–0.97, respectively). No significant association was found for total vegetables and fruits, total vegetables, or total fruits. No significant association was found for any nutrient. This study provides novel information on the association between MDD and flavonoid-rich fruits.