Tom R.P. Bishop, Grainne O'Donoghue, Matthew Pearce, Ritva Järvinen, Xu Lin, Wei Zheng, Daan Kromhout, Huaidong Du, Eiliv Lund, Joline W. J. Beulens, Nicholas J. Wareham, Miguel Ángel Martínez-González, Mika Kivimäki, Tommi Härkänen, Charlotta Rylander, Wanqing Wen, Xiao-Ou Shu, Maira Bes-Rastrollo, Jonathan E. Shaw, Norie Sawada, Sabita S. Soedamah-Muthu, Donal J. O’Gorman, Hossein Poustchi, Liang Sun, Paul Knekt, Natália Bordin Barbieri, Silvia Pastorino, Atsushi Goto, Dianna J. Magliano, Nita G. Forouhi, Tasnime N. Akbaraly, Reza Malekzadeh, Maria Inês Schmidt, Bruce Bartholow Duncan, Stephen J. Sharp, Alicja Wolk, Maryam Hashemian, Zhengming Chen, Epidemiology and Data Science, ACS - Diabetes & metabolism, ACS - Heart failure & arrhythmias, APH - Health Behaviors & Chronic Diseases, Medical and Clinical Psychology, Bes-Rastrollo, Maira [0000-0002-9139-4206], Hashemian, Maryam [0000-0002-9702-9752], Kivimaki, Mika [0000-0002-4699-5627], Malekzadeh, Reza [0000-0002-9820-6335], Martínez-González, Miguel Ángel [0000-0002-3917-9808], O’Donoghue, Gráinne [0000-0002-9126-2094], O’Gorman, Donal [0000-0002-8228-1488], Sawada, Norie [0000-0002-9936-1476], Apollo - University of Cambridge Repository, O'Donoghue, Gráinne [0000-0002-9126-2094], and O'Gorman, Donal [0000-0002-8228-1488]
The association between fish consumption and new-onset type 2 diabetes is inconsistent and differs according to geographical location. We examined the association between the total and types of fish consumption and type 2 diabetes using individual participant data from 28 prospective cohort studies from the Americas (6), Europe (15), the Western Pacific (6), and the Eastern Mediterranean (1) comprising 956,122 participants and 48,084 cases of incident type 2 diabetes. Incidence rate ratios (IRRs) for associations of total fish, shellfish, fatty, lean, fried, freshwater, and saltwater fish intake and type 2 diabetes were derived for each study, adjusting for a consistent set of confounders and combined across studies using random-effects meta-analysis. We stratified all analyses by sex due to observed interaction (p = 0.002) on the association between fish and type 2 diabetes. In women, for each 100 g/week higher intake the IRRs (95% CIs) of type 2 diabetes were 1.02 (1.01-1.03, I2 = 61%) for total fish, 1.04 (1.01-1.07, I2 = 46%) for fatty fish, and 1.02 (1.00-1.04, I2 = 33%) for lean fish. In men, all associations were null. In women, we observed variation by geographical location: IRRs for total fish were 1.03 (1.02-1.04, I2 = 0%) in the Americas and null in other regions. In conclusion, we found evidence of a neutral association between total fish intake and type 2 diabetes in men, but there was a modest positive association among women with heterogeneity across studies, which was partly explained by geographical location and types of fish intake. Future research should investigate the role of cooking methods, accompanying foods and environmental pollutants, but meanwhile, existing dietary regional, national, or international guidelines should continue to guide fish consumption within overall healthy dietary patterns.