Association between dietary vitamin B12 intake and bone mineral density in adolescents.

BACKGROUND

Vitamin B12, essential for bone health, has an unclear relationship with bone mineral density (BMD) in adolescents. This study examined this association.

METHODS

Data were drawn from the National Health and Nutrition Examination Survey (NHANES). Dietary vitamin B12 intake was assessed via 24-hour dietary recall, and BMD at the lumbar spine and femur was measured using dual-energy X-ray absorptiometry (DXA). Multiple regression models were employed to assess the relationship between vitamin B12 intake and BMD, adjusting for confounders. Subgroup analyses and interaction tests were performed, followed by sensitivity analyses, including multiple imputation for missing covariates data.

RESULTS

Among 2531 adolescents aged 12-19, higher dietary vitamin B12 intake was associated with greater BMD at both the lumbar spine and femur. A 5 mcg/day increase in vitamin B12 intake corresponded to a 12.60 mg/cm² increase in lumbar spine BMD (P = 0.009) and a 20.08 mg/cm² increase in femoral BMD (P = 0.001). Participants in the highest tertile of intake had significantly higher BMD than those in the lowest tertile. Subgroup and sensitivity analyses showed consistent results.

CONCLUSIONS

Higher vitamin B12 intake may support better BMD in adolescents, but further studies are needed to confirm these findings.

IMPACT

Higher dietary vitamin B12 intake may support bone health in adolescents during a critical growth phase. This study provides new evidence linking vitamin B12 intake with bone mineral density in a large, nationally representative cohort. The findings highlight the potential need for targeted nutritional strategies to optimize adolescent bone health. Future research should confirm these results and explore sex- and age-specific differences.