Can vitamin D3 supplementation reduce COVID-19 severity?

In a recent study published in Nutrients, researchers conducted a meta-analysis of 13 randomized clinical trials to assess the effectiveness of Vitamin D3 supplementation in reducing ICU admissions and COVID-19-related mortality.

COVID-19, caused by the SARS-CoV-2 virus, has become a global pandemic, impacting healthcare systems worldwide, with over 7 million deaths reported by February 2024. Vitamin D, known for its immunomodulatory effects, has been suggested to mitigate severe COVID-19 outcomes by regulating immune responses and reducing inflammation.

The study, following PRISMA guidelines, searched databases for relevant RCTs focusing on severe COVID-19 cases. Thirteen articles met the criteria, covering diverse demographics and control group setups. While Vitamin D3 supplementation showed a reduction in ICU admissions and COVID-19-related mortality, it did not significantly impact hospitalization length, ICU stay, or overall mortality. Publication bias was detected, suggesting underrepresentation of studies with negative outcomes.