Vitamin D and Reduced COVID-19 or Influenza Incidence

• Comparative effectiveness of oral nutritional supplements in preventing respiratory tract infections among adults: a systematic review and network meta-analysis.

  • 2025-10
  • Meta-Analysis · n = 751
  • EClinicalMedicine 88
  • • Zhixin Zhu
    • Xiaoxia Zhu
    • Yanru Chu
    • Bing Zhang
    • Yi Chen

  • PubMed: 40969681
  • DOI: 10.1016/j.eclinm.2025.103479

  3 Insights on

  • Reduced COVID-19 or Influenza Incidence

  • High evidence

  For COVID-19 or influenza prevention, high-dose vitamin D was highly effective (RR = 0.66, 95% CI: 0.51, 0.86; n = 9; moderate certainty).

  Effect

  Beneficial

  Effect size

  Moderate

  Significant

  Yes