Effect of vitamin D supplementation on bone health in Black, Asian and other non-White Ethnic adults: a systematic review and meta-analysis.

BACKGROUND

Evidence on the effects of vitamin D supplementation on bone health is inconsistent, and no systematic review has focused specifically on non-White ethnic populations, who are at higher risk of vitamin D deficiency.

OBJECTIVE

To evaluate the effects of vitamin D supplementation on bone health in non-White adults.

METHODS

CENTRAL, MEDLINE, AMED, EMBASE, EMCARE, CINAHL, and APA PsycInfo were searched from inception to September 2025. Randomised controlled trials involving all ethnic groups other than White adults receiving vitamin D supplementation of any dose or route were included. Outcomes were bone mineral density (BMD), bone turnover markers (BTMs), and fractures. Data were narratively synthesised, with meta-analyses conducted for BTMs using random-effects models. Risk of bias was assessed using the Cochrane Risk-of-Bias 2 tool.

RESULTS

Twelve trials (13 articles) involving 8,023 participants aged 18-90 years were included. Study populations comprised Black Africans, South Asians, South Koreans, and Chinese. Intervention duration ranged from 3 months to 5.3 years, with vitamin D doses from 400-6,400 IU/day. Of eight studies assessing BMD, only one study conducted in South Asians, reported significantly higher femoral neck and trochanter BMD after 12 months of vitamin D supplementation (400 IU/day) compared with placebo (p < 0.001). The primary meta-analysis showed significantly higher BALP concentrations in the vitamin D supplementation groups than in the control groups (SMD 0.96, 95% CI 0.09-1.83; p = 0.031), with substantial heterogeneity (I2 = 97.1%). However, after excluding one clinically distinct study in which both groups received risedronate, the pooled effect was attenuated and no longer statistically significant (SMD 0.64, 95% CI -0.14-1.41). Only one study examined fractures (n = 5,106) and found no significant difference between groups.

CONCLUSION

Evidence supporting vitamin D supplementation for improving bone health in non-White adults remains limited.