Statistically significant lower risk is seen for ICU admission, hospitalization, recovery, cases, and viral clearance. 10 studies from 8 independent teams in 7 countries show statistically significant improvements.
Meta analysis using the most serious outcome reported shows 49% [21‑68%] lower risk. Results are similar for Randomized Controlled Trials and higher quality studies, better after excluding studies using combined treatment, and slightly worse for peer-reviewed studies.
Results are robust — in exclusion sensitivity analysis 8 of 11 studies must be excluded to avoid finding statistically significant efficacy in pooled analysis.
Studies typically use advanced formulations for greatly improved bioavailability.
No treatment or intervention is 100% effective. All practical, effective, and safe means should be used based on risk/benefit analysis. Multiple treatments are typically used in combination, and other treatments may be more effective. The quality of non-prescription supplements can vary widely Crawford, Crighton.
All data to reproduce this paper and sources are in the appendix. Other meta analyses show significant improvements with quercetin for mortality Ziaei, ICU admission Cheema, Ziaei, and hospitalization Cheema, Ziaei.
2 meta analyses show significant improvements with quercetin for mortality
Ziaei,
ICU admission
Cheema,
Ziaei, and
hospitalization
Cheema,
Ziaei.
Covid Analysis et al., Mar 2024, preprint, 1 author.