Eating Fish and Risk of Type 2 Diabetes: A population-based, prospective follow-up study

OBJECTIVE: To investigate the relation between total fish, type of fish (lean and fatty), and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake and risk of type 2 diabetes in a population-based cohort. RESEARCH DESIGN AND METHODS: The analysis included 4,472 Dutch participants aged ≥55 years without diabetes at baseline. Dietary intake was assessed with a semiquantitative food frequency questionnaire. Hazard ratios (relative risk [RR]) with 95% CIs were used to examine risk associations adjusted for age, sex, lifestyle, and nutritional factors. RESULTS: After 15 years of follow-up, 463 participants developed type 2 diabetes. Median fish intake, mainly lean fish (81%), was 10 g/day. Total fish intake was associated positively with risk of type 2 diabetes; the RR was 1.32 (95% CI 1.02–1.70) in the highest total fish group (≥28 g/day) compared with that for non–fish eaters (P(trend) = 0.04). Correspondingly, lean fish intake tended to be associated positively with type 2 diabetes (RR highest group ]≥23 g/day] 1.30 [95% CI 1.01–1.68]; P(trend) = 0.06), but fatty fish was not. No association was observed between EPA and DHA intake and type 2 diabetes (RR highest group [≥149.4 mg/day] 1.22 [0.97–1.53]). With additional adjustment for intake of selenium, cholesterol, and vitamin D, this RR decreased to 1.05 (0.80–1.38; P(trend) = 0.77). CONCLUSIONS: The findings do not support a beneficial effect of total fish, type of fish, or EPA and DHA intake on the risk of type 2 diabetes. Alternatively, other dietary components, such as selenium, and unmeasured contaminants present in fish might explain our results.