Dietary Energy Density Predicts the Risk of Incident Type 2 Diabetes: The European Prospective Investigation of Cancer (EPIC)-Norfolk Study

OBJECTIVE—Accumulating evidence suggests that energy-dense foods predispose to obesity and that such foods may also be associated with an increased risk of type 2 diabetes, but there is limited evidence. Our aim was to investigate whether there is an independent association between dietary energy density and incidence of diabetes. RESEARCH DESIGN AND METHODS—The European Prospective Investigation of Cancer (EPIC)-Norfolk Cohort Study was a population-based prospective study of individuals aged 40–79 years at baseline. We calculated energy density for overall diet (all solids and drinks) using food frequency questionnaires. During 12 years of follow-up, we documented 725 new-onset cases of diabetes among 21,919 participants without diabetes, cancer, or cardiovascular disease at baseline. RESULTS—Baseline energy density (adjusted for age, sex, and baseline BMI) was higher in those who developed type 2 diabetes (mean 3.08 kJ/g [95% CI 3.03–3.13]) than in those who remained nondiabetic (3.01 kJ/g [3.00–3.02]) (P = 0.012). Energy density was positively associated with incident diabetes (odds ratio 1.21 per unit increase [95% CI 1.06–1.38]) adjusted for known risk factors. There was a 60% higher risk of diabetes (1.60 [1.19–2.16]) in the highest quintile of energy density (range 3.55–7.97 kJ/g) compared with the lowest quintile (1.04–2.43 kJ/g) in adjusted analysis. CONCLUSIONS—This is the first large population-based prospective study to report that an energy-dense diet may be associated with increased risk of development of diabetes, independent of baseline obesity. The potential public health impact of a low–energy-dense diet on reducing the risk of diabetes deserves further study.