Dietary pattern, inflammation, and incidence of type 2 diabetes in women.

BACKGROUND: Inflammation is considered a key mechanism leading to type 2 diabetes, but dietary exposures that lead to inflammation and diabetes are largely unknown. OBJECTIVE: Our objective was to investigate the relation between a dietary pattern associated with biomarkers of inflammation and the incidence of type 2 diabetes. DESIGN: We conducted a nested case-control study of 656 cases of type 2 diabetes and 694 controls among women in the Nurses' Health Study and 2 prospective cohort studies of 35,340 women in the Nurses' Health Study and 89,311 women in the Nurses' Health Study II who were followed for incident diabetes. RESULTS: Through the use of reduced rank regression, we identified a dietary pattern that was strongly related to inflammatory markers in the nested case-control study. This pattern, which was high in sugar-sweetened soft drinks, refined grains, diet soft drinks, and processed meat but low in wine, coffee, cruciferous vegetables, and yellow vegetables, was associated with an increased risk of diabetes (multivariate-adjusted odds ratio comparing extreme quintiles: 3.09; 95% CI: 1.99, 4.79). We identified 1517 incident cases of confirmed type 2 diabetes in the Nurses' Health Study (458,991 person-years) and 724 incident cases in the Nurses' Health Study II (701,155 person-years). After adjustment for body mass index and other potential lifestyle confounders, the relative risks comparing extreme quintiles of the pattern were 2.56 (95% CI: 2.10, 3.12; P for trend < 0.001) in the Nurses' Health Study and 2.93 (95% CI: 2.18, 3.92; P for trend < 0.001) in the Nurses' Health Study II. CONCLUSION: The dietary pattern identified may increase chronic inflammation and raise the risk of developing type 2 diabetes.