The efficacy of vitamin D supplementation in the management of childhood asthma: a systematic review and meta-analysis

This is the authors' abstract. We don't add key points for this paper.

Background: Childhood asthma is a major public health concern. Current evidence regarding vitamin D supplementation in childhood asthma remains inconsistent, particularly with respect to pulmonary function. This study comprehensively evaluates the role of vitamin D supplementation in childhood asthma, with a particular focus on lung function. Method: PubMed, EMBASE, Web of Science, and the Cochrane Library were searched through October 31, 2025 for RCTs. Data were extracted and analyzed using FEV1 (%) as the primary outcome measure, and FVC (%), FEV1/FVC, PEF, FeNO, cACT, and IgE as secondary outcome measures. Results: = 1239) were included. We did not find evidence that vitamin D supplementation improves lung function [FEV1 (%): SMD: 0.39, 95% CI: -0.13 to 0.92; FVC (%): SMD: 0.13, 95% CI: -0.73 to 0.98; FEV1/FVC: MD: 0.56, 95% CI: -7.24 to 8.35; PEF: MD: -3.69, 95% CI: -9.71 to 2.34] or cACT scores (MD: 0.16, 95% CI: -0.55 to 0.88), nor does it reduce FeNO or IgE levels (SMD: -0.14, 95% CI: -0.61 to 0.33) in children with asthma. Conclusion: Vitamin D supplementation showed no overall benefit for lung function, IgE levels, FeNO, or cACT scores in children with asthma. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD420251270660.