Vitamin D and Its Analogs in Treatment of Mild to Moderate Alopecia Areata: Systematic Review and Meta-Analysis

This systematic review and meta-analysis assessed the efficacy and safety of vitamin D3 and its analogs in treating mild to moderate alopecia areata (AA) across nine studies with 621 participants. The findings indicated a therapeutic efficacy of 53.75% for vitamin D3 treatments, with intralesional vitamin D3 being more effective than placebo in achieving significant hair regrowth. Topical vitamin D3 analogs also reduced the Severity of Alopecia Tool (SALT) score, though not significantly compared to placebo. Combining vitamin D3 analogs with treatments like corticosteroids or narrowband UVB enhanced therapeutic effects. The studies reported mild adverse effects and low recurrence rates, suggesting vitamin D3 as a stable treatment option, though more effective when used as an adjuvant therapy rather than alone. The study calls for standardized protocols to improve future research consistency.