Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) dietary exposure is associated with an increased risk of type 2 diabetes in the European prospective investigation into cancer and nutrition (EPIC) cohort.

• Dioxins and PCBs are highly toxic and >90 % of human exposure is due to food consumption. • Existing evidence links blood dioxins/PCBs to T2DM, but studies on dietary exposure are lacking. • Our study found that dietary exposure to NDL-PCBs was associated with an increased risk of T2DM. • This association remained consistent across various stratified and sensitivity analyses. • Further efforts are needed to reduce food contamination of dioxins and PCBs to lower T2DM risk. The aim of the present study was to investigate the association between dietary exposures to dioxins, dioxin-like polychlorinated biphenyls (DL-PCBs) and non-dioxin-like polychlorinated biphenyls (NDL-PCBs) and the incidence of type 2 diabetes mellitus (T2DM) in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. This prospective cohort study with a median 11.7 years of follow-up, included 318,416 individuals recruited in 21 centers in eight countries. Dietary intake of dioxins and PCBs was calculated by combining EPIC food consumption data with food contamination data from the European Food Safety Authority (EFSA). To identify incident cases of T2DM, a thorough review of various sources including self-reported information, linkage to primary and secondary care registers, drug registers, hospital admissions, and mortality data was conducted. Associations between dietary intake of dioxins and PCBs and T2DM were evaluated using multivariable Cox regressions. Higher T2DM risk was observed for higher estimated dietary intake of non-dioxin-like PCBs (NDL-PCBs; HR per 1 SD increment = 1.03 [95 %CI 1.01;1.04], and HR (Q4 vs Q1) = 1.15 [1.08;1.22], P -trend < 0.001). The results were consistent in analyses stratified by gender, body mass index, country, median follow-up, or self-reported hypertension and hyperlipidemia, as well as when adjusting for fat intake. No consistent association was observed between dioxins+DL-PCBs intake and T2DM risk. Results obtained in this large European prospective study indicate a positive and linear association between dietary intake of NDL-PCBs and risk of T2DM. This association remained consistent across various stratified and sensitivity analyses. Further studies are warranted to better understand the biological mechanisms underlying this association. [ABSTRACT FROM AUTHOR]