Plant-focused diets may decelerate epigenetic aging processes

A new research paper was published in Volume 18 of Aging-US on March 20, 2026, titled "Plant-based dietary patterns are associated with slower epigenetic aging."

Led by first and corresponding author Hyunju Kim from the Department of Epidemiology and the Cardiovascular Health Research Unit, Department of Medicine, University of Washington, the study examined whether four plant-based diet indices - overall PDI, provegetarian diet, healthy PDI, and unhealthy PDI - were associated with DNA methylation-based measures of epigenetic aging. The authors analyzed data from the Atherosclerosis Risk in Communities (ARIC) Study (n = 2,810) and the National Health and Nutrition Examination Survey (NHANES, n = 2,056), and assessed associations with GrimAge2, HannumAge, and PhenoAge. 

The researchers found that each standard deviation higher in the overall PDI, provegetarian diet, and healthy PDI was associated with decelerated GrimAge2, while higher overall PDI and provegetarian diet were also associated with decelerated PhenoAge and HannumAge. By contrast, unhealthy PDI was not significantly associated with epigenetic aging. The findings suggest that plant-rich dietary patterns, especially those emphasizing healthier plant foods, may be linked to slower biological aging in largely non-vegetarian populations.

"No significant association was observed for unhealthy PDI and any of the DNA methylation-based aging."

The authors note that these are observational data and do not establish causality. They call for longitudinal and interventional studies to determine whether sustained adherence to healthy plant-based dietary patterns can directly influence epigenetic aging and related health outcomes over time.