Association between the oxidative balance score and biological aging measured by epigenetic clock: insight from the NHANES 1999-2002

BACKGROUND: Oxidative stress is a key factor leading to oxidative damage in cells and tissues, and is a major driving force behind aging and various age-related diseases. Epigenetic clock and oxidative balance score (OBS) serve as reliable indicators for assessing an individual's aging process and oxidative stress levels, respectively. However, no study has comprehensively assessed the association between epigenetic clock and OBS. METHODS: This study analysed 1,797 subjects from the 1999-2002 National Health and Nutrition Examination Survey (NHANES). Multivariate regression models were used to assess the relationship between OBS and epigenetic age as well as epigenetic age acceleration (EAA). Restricted cubic spline (RCS) analyses were used to visualize the dose-response relationship between OBS and EAA. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations. RESULTS: Multiple linear regression analyses showed that higher OBS levels were significantly associated with lower epigenetic age. Further analyses showed that both the dietary OBS and the lifestyle OBS were significantly negatively correlated with epigenetic age. RCS analysis revealed a significant negative linear dose-response relationship between OBS and EAA. The association between OBS and EAA was homogeneous across subgroups. CONCLUSIONS: This study suggests higher OBS levels are associated with reduced epigenetic age and decelerated biological aging, and antioxidant-rich diets and lifestyles may delay biological aging.