Dietary patterns and risk of incident type 2 diabetes in the multi-ethnic study of atherosclerosis (MESA)

OBJECTIVE - We characterized dietary patterns and their relation to incident type 2 diabetes in 5, 011 participants from the Multi-Ethnic Study of Atherosclerosis (MESA). RESEARCH DESIGN AND METHODS - White, black, Hispanic, and Chinese adults, aged 45-84 years and free of cardiovascular disease and diabetes, completed food frequency questionnaires at baseline (2000-2002). Incident type 2 diabetes was defined at three follow-up exams (2002-2003, 2004-2005, and 2005-2007) as fasting glucose > 126 mg/dl, self-reported type 2 diabetes, or use of diabetes medication. Two types of dietary patterns were studied: four empirically derived (principal components analysis) and one author-defined (low-risk food pattern) as the weighted sum of whole grains, vegetables, nuts/seeds, low-fat dairy, coffee (positively weighted), red meat, processed meat, high-fat dairy, and soda (negatively weighted). RESULTS - The empirically derived dietary pattern characterized by high intake of tomatoes, beans, refined grains, high-fat dairy, and red meat was associated with an 18% greater risk (hazard ratio per 1-score SD 1.18 [95% CI 1.06-1.32]; P _trend = 0.004), whereas the empirically derived dietary pattern characterized by high intake of whole grains, fruit, nuts/seeds, green leafy vegetables, and low-fat dairy was associated with a 15% lower diabetes risk (0.85 [0.76-0.95]; P _trend = 0.005). The low-risk food pattern was also inversely associated with diabetes risk (0.87 [0.81-0.99]; P _trend = 0.04). Individual component food groups were not independently associated with diabetes risk. Associations were not modified by sex or race/ethnicity. CONCLUSIONS - Multiple food groups collectively influence type 2 diabetes risk beyond that of the individual food groups themselves.