Abstract
BACKGROUND: Plant-based diets are recommended for chronic disease prevention, yet there has been little focus on plant-based diet quality among participants of South Asian ancestry who consume a predominantly plant-based diet. OBJECTIVES: We evaluated cross-sectional and prospective associations between plant-based diet quality and cardiometabolic risks among participants of South Asian ancestry who are living in the United States. METHODS: We included 891 participants of South Asian ancestry who completed the baseline visit in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study. The prospective analysis included 735 participants who completed exam 2 (∼5 years after baseline). The plant-based diet quality was assessed using 3 indices: an overall plant-based diet index (PDI) that summarizes the consumption of plant foods, a healthy PDI (hPDI) that measures consumption of healthy plant foods, and an unhealthy PDI (uPDI) that reflects consumption of less healthy plant foods. RESULTS: At baseline, the PDI score was inversely associated with fasting glucose. We observed inverse associations between PDI and hPDI scores and HOMA-IR, LDL cholesterol, weight, and BMI (all P values < 0.05). Higher scores on the hPDI, but not PDI, were associated with lower glycated hemoglobin, higher adiponectin, a smaller visceral fat area, and a smaller pericardial fat volume. Each 5-unit higher hPDI score was associated with lower likelihoods of fatty liver (OR: 0.76; 95% CI: 0.64, 0.90) and obesity (OR: 0.88; 95% CI: 0.80, 0.97). There were no associations between uPDI scores and cardiometabolic risks. Prospectively, after covariate adjustment for baseline values, each 5-unit higher hPDI score was associated with an 18% lower risk of incident type 2 diabetes (OR: 0.82; 95% CI: 0.67, 1.00). CONCLUSIONS: A higher intake of healthful plant-based foods was associated with a favorable cardiometabolic risk profile. Dietary recommendations to lower chronic disease risks among participants of South Asian ancestry should focus on the quality of plant-based foods.