Associations between dietary exposure to dioxins and polychlorinated biphenyls (PCBs) and Longitudinal changes in weight and waist circumference– an EPIC study

BACKGROUND: Obesity is a growing global health concern. Some evidence suggests that exposure to polychlorinated biphenyls (PCBs) and dioxins, may play a role in weight gain, but human prospective data are limited and have shown inconsistent results. Therefore, this study investigate the association between dietary exposure to dioxins and PCBs and changes in weight and in waist circumference after 5 years of follow-up in a large prospective cohort. METHOD: We included 215,556 participants recruited between 1992 and 2000; of whom 99,046 provided data on waist circumference. Body weight or waist circumference were measured at recruitment and self-reported at follow-up. Intakes of dioxins and PCBs were estimated using country-specific dietary questionnaires collected at baseline, and food contamination concentrations based on a European Food Safety Authority database. Associations were estimated using multilevel mixed linear regression models. RESULTS: Higher intake of both dioxins and dioxin-like PCBs (dioxins + DL-PCBs) (Q4vsQ1 = 0.07kg/5-years (95%CI 0.01, 0.13)), and non-dioxin like PCBs (NDL-PCBs) (Q4vsQ1 = 0.27kg/5-years (95%CI 0.20, 0.35), p-trend