Fish consumption, intake of fats and cognitive decline at middle and older age: the Doetinchem Cohort Study

Purpose: To get insight in the impact of fish and fat intake in the prevention of accelerated cognitive decline with ageing, we tested associations between fish and different fat intakes and 5-year change in cognitive functions. Methods: In 2612 men and women of the Doetinchem Cohort Study, aged 43–70 years at baseline, dietary intake (including fish consumption) and cognitive function were assessed at baseline and at 5-year follow-up. Average fish consumption (frequency) and intakes (as energy percentages) of total fat, saturated, mono unsaturated, and polyunsaturated fatty acids (PUFA), linoleic, docosahexaenoic, eicosapentaenoic, and a-linolenic acid (ALA), and cholesterol were averaged over baseline and follow-up. Intakes were studied in relation to 5-year change in global cognitive function, memory, information processing speed, and cognitive flexibility, using ANCOVA and multivariate linear regression analyses. Results: No consistent association between (fatty) fish consumption and cognitive decline was observed. Higher cholesterol intake was associated with faster cognitive decline (p < 0.05). Higher n-3 PUFA (especially ALA) intake was associated with slower decline in global cognitive function and memory (p < 0.01). Intakes of other fatty acids were not associated with cognitive decline. Conclusions: Higher cholesterol intake was detrimental, while higher ALA intake was beneficial for maintaining cognitive function with ageing, already at middle age.