Statistically significant lower risk is seen for mortality, ICU admission, hospitalization, and recovery. 24 studies from 24 independent teams in 12 countries show significant improvements.
Meta analysis using the most serious outcome reported shows 21% [14‑27%] lower risk. Results are similar for Randomized Controlled Trials, higher quality studies, and peer-reviewed studies. Clinical outcomes suggest benefit while viral and case outcomes do not, consistent with an intervention that aids the immune system or recovery but may have limited antiviral effects. Early treatment is more effective than late treatment.
Results are robust — in exclusion sensitivity analysis 30 of 72 studies must be excluded to avoid finding statistically significant efficacy in pooled analysis.
6 RCTs with 1,420 patients have not reported results (up to 3 years late).
The European Food Safety Authority has found evidence for a causal relationship between the intake of vitamin C and optimal immune system function1,2.
Early cessation of high dose IV treatment may result in a detrimental rebound effect3. Ongoing treatment is more effective than early cessation: 33% [22‑42%] vs. 16% [-31‑46%].
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 are more effective. The quality of non-prescription supplements can vary widely and the quantity of the active ingredient may be significantly lower than stated4-6.
All data to reproduce this paper and sources are in the appendix. 6 other meta analyses show significant improvements with vitamin C for mortality7-10, progression11, severity7, and cases12.
6 meta analyses show significant improvements with vitamin C for mortality
1-4,
progression
5,
severity
1, and
cases
6.
Covid Analysis et al., Oct 2024, preprint, 1 author.
