Plant-based dietary patterns and incident diabetes in the Atherosclerosis Risk in Communities (ARIC) Study

Objective: Plant-based dietary patterns emphasize plant foods and minimize animal-derived foods. We investigated the association between plant-based dietary patterns and diabetes in a community-based U.S. sample of Black and White adults. Research Design and Methods: We included middle-aged adults from the Atherosclerosis Risk in Communities (ARIC) Study without diabetes at baseline who completed a food frequency questionnaire (n=11,965). We scored plant-based diet adherence according to three indices: overall, healthy, and unhealthy plant-based diet indices. Higher overall plant-based diet index scores represent greater intakes of all plant foods and lower intakes of animal-derived foods. Higher healthy plant-based diet index scores represent greater healthy plant food intake and lower intakes of animal-derived and unhealthy plant foods. Higher unhealthy plant-based diet index scores represent greater unhealthy plant food intake and lower intakes of animal-derived and healthy plant foods. We used Cox regression to estimate hazard ratios for incident diabetes (defined by self-reported diagnosis, medication use, or elevated blood glucose) associated with each index. Results: Over a median follow-up of 22 years, we identified 4,208 diabetes cases. Higher overall plant-based diet index scores were associated with a lower risk of diabetes (quintile 5 versus 1: HR 0.89, 95% CI: 0.80, 0.98; P-trend=0.01). Healthy plant-based diet index scores were also inversely associated with diabetes risk (quintile 5 versus 1: HR 0.85, 95% CI: 0.77, 0.94; P-trend<0.001). Unhealthy plant-based diet index scores were not associated with diabetes risk. Conclusions: A dietary pattern that minimizes animal-derived foods and emphasizes plant foods may reduce diabetes risk.