Adherence to the EAT-Lancet diet in relation to mortality and exposure to food contaminants in population-based cohorts of Swedish men and women

BACKGROUND: The EAT-Lancet diet was created to support dietary transition towards sustainable diets. Current evidence indicates that adherence to the EAT-Lancet diet may reduce mortality risk, yet how adherence may impact dietary exposure to food contaminants remains unexplored. We aimed to estimate the association between adherence to the EAT-Lancet diet and i) all-cause, cardiovascular-, and cancer-mortality and ii) predicted dietary exposure to the following food contaminants: cadmium, methylmercury, polychlorinated biphenyls (PCBs), and pesticide residues. METHODS: We used self-reported dietary data from a 96-item food frequency questionnaire of two population-based cohorts - the Cohort of Swedish Men (n = 35,687) and the Swedish Mammography Cohort (n = 32,488). The EAT-Lancet Adherence Index (EAI) was created by scoring consumption of the 14 dietary components included in the EAT-Lancet diet (totalling 0-14 points). Cox proportional hazards regression models were applied to assess the association between EAI and mortality outcomes, presented as multivariable-adjusted hazard ratios (HR) and 95 % confidence intervals (CI). Descriptive statistics were used to characterise predicted exposure to food contaminants, and the correlations between EAI and food contaminants assessed using Spearman's rank correlation. RESULTS: Increased adherence to the EAT-Lancet diet was associated with a lower risk of all-cause mortality (per 3-point increase in EAI: HR = 0.93; CI:0.90,0.97 and HR = 0.91; CI:0.87,0.95 for men and women, respectively) and cardiovascular-mortality (corresponding HR = 0.94; CI:0.88,1.00 and HR = 0.93; CI:0.87,1.00). No clear association was found with cancer-mortality. Increasing EAI was correlated with increased predicted dietary exposure to cadmium, methylmercury, PCBs, and pesticide residues and their median predicted dietary exposures were greater in the high adherence group, compared to the low adherence group. CONCLUSION: High adherence to the EAT-Lancet diet is associated with a reduction in risk of all-cause and cardiovascular-mortality, but also increased dietary exposure to food contaminants.