Significantly lower risk is seen for recovery and cases. 7 studies from 6 independent teams in 3 countries show significant benefit.
Meta analysis using the most serious outcome reported shows 36% [6‑56%] lower risk. Results are similar for Randomized Controlled Trials, higher quality studies, and peer-reviewed studies. Results are consistent with early treatment being more effective than late treatment.
6 sufficiency studies analyze outcomes based on serum levels, showing 80% [52‑92%] lower risk for patients with higher vitamin A levels.
In exclusion sensitivity analysis, statistical significance is lost after excluding 2 of 14 studies in pooled analysis.
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. The quality of non-prescription supplements varies widely3,4. All data and sources to reproduce this analysis are in the appendix.
Covid Analysis et al., Dec 2024, preprint, 1 author.