Abstract MP14: A Prospective Study of the Association Between Plant-Based Dietary Patterns and Incident Type 2 Diabetes in Women
Studies of dietary determinants of type 2 diabetes (T2D) have found inverse associations with several plant-foods, and positive associations with some animal-foods, raising the question of whether plant-based diets are protective against T2D. However, as not all plant-foods are equally beneficial, the healthiest version of a plant-based diet needs to be identified.
We assessed the hypothesis that plant-based diets are associated with lower T2D risk. We prospectively observed 74,248 women from the Nurses’ Health Study (1984-2012) who were free of diabetes, cardiovascular disease, and cancer at baseline. We created a total plant-based diet index (PDI) and a healthy or ‘alternate’ plant-based diet index (aPDI) using dietary data collected every 4 years with a food frequency questionnaire. Individual foods were aggregated into healthy plant-food groups (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, and tea/coffee), unhealthy plant-food groups (fruit juices, refined grains, potato/fries, margarine, sugar sweetened beverages, and sweets) and animal-food groups (animal fats, dairy, egg, fish, and processed & fresh red meat & poultry). For PDI, positive scores were given to all plant-foods, and negative scores to the animal-foods. For aPDI, positive scores were given to the healthy plant-foods, and reverse scores to the unhealthy plant-foods and the animal-foods.
We documented 8119 incident T2D cases during 1,761,104 person-years of follow-up. In multivariable-adjusted analysis, both PDI and aPDI were inversely associated with T2D (PDI [HR for extreme deciles: 0.61, 95% CI: 0.55-0.68; p trend<0.0001]; aPDI [HR for extreme deciles: 0.49, 95% CI: 0.44-0.55; p trend<0.0001]). The association with PDI was attenuated when body mass index was also included in the model (HR for extreme deciles: 0.91, 95% CI: 0.82-1.02; p trend: 0.009). The inverse association observed with aPDI was only slightly attenuated after additionally adjusting for body mass index [HR for extreme deciles: 0.56, 95% CI: 0.50-0.63; p trend<0.0001]. Similar associations were found across all strata in analyses stratified by obesity, physical activity, and family history of T2D. Our data suggest that an overall plant-based diet was associated with lower T2D risk but the associations were stronger for a healthier version of the plant-based diet.
Author Disclosures: A. Satija: None. S.N. Bhupathiraju: None. W.C. Willett: None. J.E. Manson: None. Q. Sun: None. F.B. Hu: None.
- © 2015 by American Heart Association, Inc.