Vitamin A for COVID-19: real-time meta-analysis of 21 studies (14 treatment studies and 7 sufficiency studies) (Version 37)

Significantly lower risk is seen for hospitalization, recovery, and cases. 8 studies from 7 independent teams in 4 countries show significant benefit.

Meta-analysis using the most serious outcome reported shows 33% [12‑49%] lower risk. Results are similar for higher quality and peer-reviewed studies and better for Randomized Controlled Trials. Results are consistent with early treatment being more effective than late treatment.

7 sufficiency studies analyze outcomes based on serum levels, showing 85% [62‑94%] lower risk for patients with higher vitamin A levels.

Results are robust—in worst case exclusion sensitivity analysis 5 of 14 studies must be excluded before statistical significance is lost.

Control Vitamin A

The European Food Safety Authority has found evidence for a causal relationship between the intake of vitamin A and optimal immune system function1,2.

No treatment is 100% effective. Protocols combine safe and effective options with individual risk/benefit analysis and monitoring. Other treatments are more effective. Dietary sources may be preferred. The quality of non-prescription supplements varies widely3-5. Administration with a high-fat meal increases the bioavailability of vitamin A, and may aid distribution to target tissues. All data and sources to reproduce this analysis are in the appendix.