Vitamin D Supplementation and COVID-19 Outcomes
Dissanayake HA, de Silva NL, Sumanatilleke M, et al
Scientific Reports • April 2022
Plain Language Summary
This analysis of multiple studies found that people with low vitamin D levels were more likely to have severe COVID-19 illness and higher risk of death. While this doesn’t prove that vitamin D prevents COVID-19, it suggests that maintaining adequate vitamin D levels (30-50 ng/mL in blood) may support immune function during respiratory infections. Taking vitamin D supplements may be particularly important for those who are deficient.
Key Findings
- 1Vitamin D deficiency was associated with increased risk of severe COVID-19 (OR 1.64, 95% CI 1.30-2.09)
- 2Lower vitamin D levels correlated with higher mortality risk
- 3Supplementation before or early in infection showed potential benefit
- 4Optimal serum levels of 30-50 ng/mL appeared most protective
Abstract
This systematic review and meta-analysis evaluated the association between vitamin D status and COVID-19 outcomes. The analysis included observational studies and clinical trials examining vitamin D deficiency, supplementation, and COVID-19 severity, ICU admission, and mortality.
Study Limitations
- High heterogeneity among included studies
- Confounding factors not fully controlled
- Most evidence from observational studies
- Varying definitions of vitamin D deficiency