Serum vitamins and trace elements in vitiligo patients: A systematic review and meta-analysis of observational studies

Vitiligo is one of the most common pigmentary skin disorders, which significantly impacts the quality of life. The aetiology and pathophysiology of vitiligo are still unclear, but one of the proposed mechanisms is oxidative damage interrupting melanogenesis. The purpose of this study was to demonstrate the serum levels of trace elements and vitamins and to systematically review the evidence comparing vitiligo patients with a healthy group. We comprehensively retrieved all studies related to vitiligo and the serum levels of vitamins and minerals from databases such as PubMed, EMBASE, Scopus, Web of Science, Magiran, SID and ISC up to December 2022. Quality assessment and data extraction were conducted by two independent reviewers. Pooled standard mean differences with 95% confidence intervals were estimated using random-effects models. Our meta-analysis revealed no significant differences in serum levels of Vitamin B12 and copper. It was concluded that serum concentrations of Vitamin D, Vitamin E, and zinc were lower in vitiligo patients. Conversely, these patients exhibited higher levels of selenium and folic acid compared with healthy individuals. These results might affect the potential use of vitamin and mineral supplementation in vitiligo treatment.