Association between vitamin intake and biological aging: evidence from NHANES 2007-2018

The combined effect of vitamin mixture on biological aging, along with the specific contribution of individual components, remains unclear. This study investigated the associations between a mixture of 11 dietary vitamins and biological aging.

This cross-sectional study included 15050 adults from NHANES 2007-2018. Daily intakes of 11 vitamins were estimated using the multiple source method to account for within-person variation from two 24 -h recalls, incorporating both food and supplement contributions. Total vitamin intake was calculated as their sum. Biological aging was assessed using three established indicators: KDM-acceleration and PhenoAge-acceleration (derived as regression residuals of biological age on chronological age), and homeostatic dysregulation (HD, a composite physiological score). Multiple linear regression, restricted cubic spline regression, and quantile g-computation were used to assess individual and joint associations.

The median age was 51.0 years, and 51.5% were female. Higher total vitamin intake was significantly associated with reduced biological aging (KDM-acceleration: β = -1.281; PhenoAge-acceleration: β = -1.379; HD: β = -0.046). Dose-response relationships were linear (all P_nonlinear > 0.05). Stratified analyses revealed stronger associations in males and individuals with comorbidity. Vitamin C was the primary protective component, followed by vitamin B2.

Higher intake of dietary vitamin mixture was associated with slower biological aging, with vitamin C as the key protective driver. These findings support recommending vitamin-rich diets to promote healthy aging.