Adherence to the EAT-Lancet Planetary Health Diet and Cardiometabolic Risk Markers in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study

Background: The global food system significantly impacts environmental and human health, contributing to substantial greenhouse gas emissions. Objective: We examined associations between a novel Planetary Health Diet Index (PHDI) that reflects adherence to the EAT-Lancet recommendations and cardiometabolic risk in a cohort of South Asians. Methods: We analyzed data from MASALA study participants with baseline (n = 891) and 5-y follow-up (n = 735) data. The PHDI comprised 15 food components and ranged from 0 to a maximum of 140, with higher scores indicating greater adherence to the PHDI. We used multivariable linear and logistic regression models to examine cross-sectional and prospective (5-y) associations between baseline PHDI and cardiometabolic risk factors, adjusting for demographic, health, and lifestyle factors and baseline values of the outcome (prospective analyses only). Results: Among MASALA study participants (47% female, mean age 55 y), the mean PHDI score was 88.8 (SD 9.47). Prospectively, higher PHDI was associated with lower percentage difference in fasting glucose (−0.29 ± 0.15 %), glycated hemoglobin (HbA1c) (−0.08 ± 0.04%), higher high-density lipoprotein (0.40 ± 0.17 mmol/L), lower body weight (−0.37 ± 0.12 kg), body mass index (BMI) (−0.08 ± 0.03 kg/m²), waist circumference (−0.49 ± 0.17 cm), and systolic blood pressure (−0.65 ± 0.30 mmHg) (P < 0.05 for all). Each 10-unit higher PHDI was associated with a 20% lower likelihood of incident type 2 diabetes (OR [95% CI]: 0.80 [0.54, 0.86]). Cross-sectionally, at baseline, 10 unit higher PHDI was associated with (β ± SE) lower percentage difference in fasting glucose (−0.45 ± 0.22 %) and HbA1c (−0.49 ± 0.22%), lower LDL (−0.015 ± 0.007 mmol/L), CRP (−5.40 ± 2.42 ug/L), higher adiponectin (4.67 ± 2.02 mg/dL), lower body weight (−0.59 ± 0.26 kg), BMI (−0.27 ± 0.11 kg/m²), waist circumference (−025 ± 0.29 cm), visceral fat (−1.37 ± 1.32 cm²), and pericardial fat (−0.58 ± 0.43 cm³) (P < 0.05 for all). Higher PHDI scores were associated with lower odds of obesity (OR [95% CI]: 0.80 [0.71, 0.92]) and overweight (0.77 [0.74, 0.85]). Conclusions: Greater adherence to a planetary healthy diet was associated with lower cardiometabolic risk factors and risk of incident type 2 diabetes.