Sunscreen and 25-Hydroxyvitamin D Levels: Friends or Foes? A Systematic Review and Meta-Analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of human studies
PubMed 40246233 · doi:10.1016/j.eprac.2025.03.014
What was done
A systematic review and meta-analysis of PubMed/MEDLINE, Scopus, and Web of Science databases (inception to November 2024) evaluated the impact of sunscreen use on serum 25-hydroxyvitamin D (25(OH)D) concentrations following PRISMA guidelines. The review included 22 studies in the qualitative synthesis and 7 studies in the meta-analysis.
What was found
In vitro studies showed sunscreen blocks UV-B radiation. Meta-analysis of 7 studies with 9,470 participants showed that sunscreen use was associated with a significant reduction in serum 25(OH)D levels (standardized mean difference = -2 ng/mL, 95% CI: -3 to -1 ng/mL). Study heterogeneity was low to moderate (I² = 37%, P = .15).
Why it matters
This review provides quantitative pooled evidence that sunscreen application results in a modest, measurable reduction in circulating vitamin D levels. It helps frame public health discussions reconciling photoprotection with vitamin D sufficiency.
Limits
Only 7 of 22 included studies provided quantitative data for meta-analysis. The abstract combines observational and interventional studies and lacks subgroup details on sunscreen SPF, application adherence, latitude, seasonality, and clinical endpoints beyond surrogate serum 25(OH)D levels.