MONDAY, Aug. 3, 2026 (HealthDay News) -- The associations of healthy or unhealthy plant-based diet indices (hPDI or uPDI) with risks of cardiovascular disease (CVD), type 2 diabetes (T2D), and mortality seem not to vary based on food processing levels, according to a study presented at NUTRITION 2026, the annual meeting of the American Society for Nutrition, held from July 25 to 28 in Washington, D.C.
Xiaowen Wang, Ph.D., from the Harvard T.H. Chan School of Public Health in Boston, and colleagues used data from three large U.S. cohorts comprising 160,690 women and 42,585 men to distinguish health effects according to food processing levels. By jointly considering PDI classification and ultraprocessed food (UPF) status, six plant-based diet indices were constucted: UPF-PDI, non-UPF-PDI, UPF-hPDI, non-UPF-hPDI, UPF-uPDI, and non-UPF-uPDI.
Overall, 26,209 CVD cases; 21,006 T2D cases; and 55,493 deaths were documented. The researchers found that comparing the highest versus the lowest quintiles of scores, there were significant associations seen for UPF-hPDI and non-UPF-hPDI with lower risk of CVD (hazard ratios, 0.86 and 0.82, respectively), T2D (hazard ratios, 0.67 and 0.66, respectively), and mortality (hazard ratios, 0.89 and 0.93, respectively). In contrast, there were associations seen for non-UPF-uPDI and UPF-uPDI with significantly higher risks of CVD (hazard ratios, 1.21 and 1.17, respectively) and T2D (hazard ratios, 1.14 and 1.11, respectively); a significant association was seen for UPF-uPDI with higher mortality (hazard ratio, 1.07).
"People should prioritize the quality of foods rather than focusing solely on the level of processing," Wang said in a statement. "Aim for more nutrient-dense, high-quality foods to help lower your risk of chronic diseases."
