Association Between Serum 25-Hydroxyvitamin D and Blood Pressure in Young Adults

Background: Vitamin D has been associated with blood pressure across the life course in observational studies, although effect sizes are generally modest and findings are not fully consistent. We examined the association between serum 25-hydroxyvitamin D 25(OH)D concentrations and multiple blood pressure indices in a community-based cohort of young adults. Methods: We conducted a cross-sectional analysis within the Young Taiwanese Adults (YOTA) cohort, restricting the sample to adults aged 18–45 years with complete serum 25(OH)D and blood pressure data. Serum 25(OH)D was modeled as a continuous variable and additionally examined using predefined concentration categories. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were assessed using standardized protocols. Multivariable linear regression models evaluated associations, with sequential adjustment for demographic, anthropometric, cardiometabolic, and lifestyle covariates. Restricted cubic spline models assessed potential nonlinearity. Results: Among 923 participants, higher serum 25(OH)D concentrations were modestly and linearly associated with lower SBP, DBP, and MAP after multivariable adjustment. Each 10 ng/mL increase in serum 25(OH)D was associated with a 1.07 mmHg lower SBP, a 1.19 mmHg lower DBP, and a 1.22 mmHg lower MAP. Associations remained consistent in sensitivity and subgroup analyses. Conclusions: In young adults, higher serum 25(OH)D concentrations were modestly associated with lower blood pressure indices. These findings confirm prior observational evidence of modest inverse associations between serum 25-hydroxyvitamin D concentrations and blood pressure and extend these observations to a relatively healthy young adult population. Prospective studies are required to clarify temporality and clinical relevance.