Quantity and variety of fruit and vegetable intake in midlife and cognitive impairment in late life: a prospective cohort study

There is limited evidence on fruit and vegetable intake in relation to cognitive function. This study aimed to evaluate the associations of quantity and variety in fruit and vegetable intake in midlife with cognitive impairment in late life. We used data from 16 737 participants of the Singapore Chinese Health Study, a population-based cohort study. The participants provided dietary data at recruitment at median age of 52·5 (range: 45–74) years and also participated in the third follow-up interview 20 years later at median age of 72·2 (range: 61–96) years. Quantity and variety of fruits and vegetables consumed at baseline were measured using a validated FFQ. Cognitive impairment at the third follow-up was defined using a Singapore-modified version of Mini-Mental State Examination. About 14·3 % participants had cognitive impairment. In multivariable logistic regression models, comparing extreme quartiles for intake of fruits and vegetables combined, the OR (95 % CI) associated with cognitive impairment was 0·83 (95 % CI: 0·73, 0·95; P-trend = 0·006) for quantity and 0·76 (95 % CI: 0·67, 0·87; P-trend< 0·001) for variety scores. Independently, those with increased variety of fruit intake or higher quantity of vegetable intake also had significantly 22 % and 15 % reduced odds of cognitive impairment, respectively. Finally, compared with those with low intake for both quantity and variety, those with both high quantity and variety for fruits and vegetables had 23 % reduction in odds of cognitive impairment. In conclusion, increase in quantity and variety of fruits and vegetables in midlife may reduce the risk of cognitive impairment in late life.