Differences in the Association of Select Dietary Measures With Risk of Incident Type 2 Diabetes
OBJECTIVE To evaluate associations between a broad range of approaches to classifying diet and incident type 2 diabetes in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study.
RESEARCH DESIGN AND METHODS This study included 8,750 Black and White adults without diabetes at baseline. Diabetes was defined as fasting glucose>=70 mmol/L, or random glucose>=111 mmol/L, or use of diabetes medications. The exposures were diet scores including: Mediterranean, DASH, Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND), Dietary Inflammatory Index (DII), Dietary Inflammation Score (DIS) and empirical dietary patterns (plant-based and Southern) determined using data collected with Block98 food frequency questionnaire. Modified Poisson regression was used to assess the association of dietary measures with risk of incident type 2 diabetes, with models adjusted for total energy intake, demographics, lifestyle factors, and waist circumference.
RESULTS There were 1026 cases of incident type 2 diabetes during follow-up (11.7%). Adherence to the Southern dietary pattern was the pattern most strongly associated with risk of incident type 2 diabetes after adjustment for demographics and lifestyle (Q5 vs. Q1: RR=1.95; 95% CI=1.57 – 2.41). Of the diet scores, DIS (Q5 vs Q1 RR=1.41) and MIND (Q1 vs Q5 RR=1.33) demonstrated anti-inflammatory diets had strongest associations with lower diabetes incidence.
We found associations of several dietary approaches with incident type 2 diabetes. Investigation into mechanisms driving the association with the Southern dietary pattern is warranted. Further research of dietary inflammation scores (DIS and DII), and MIND diet score, should be considered in dietary recommendations for diabetes prevention.