Impact of high-dose vitamin C on the mortality, severity, and duration of hospital stay in COVID-19 patients: A meta-analysis

Health Sci Rep. 2022 Aug 8;5(5):e762. doi: 10.1002/hsr2.762. eCollection 2022 Sep.


Background and aims: Vitamin C has been predicted to be effective as an antioxidant in treating various ailments, including viral infections such as pervasive coronavirus disease (COVID-19). With this meta-analysis, we looked to ascertain the relationship between high-dose vitamin C administration and mortality, severity, and length of hospitalization of COVID-19 patients.

Methods: We collected articles from PubMed, Google Scholar, ScienceDirect, SAGE, and Cochrane databases between January 1, 2020, and May 30, 2022. Odds ratio (ORs) with corresponding 95% confidence interval (CI) and p value were calculated to assess the connection of high-dose vitamin C in COVID-19 patients' mortality and severity. The length of hospitalization was calculated and pooled with the mean difference (MD), 95% CI, and p value. Review manager 5.3 was used to carry out this meta-analysis.

Results: This meta-analysis included 15 complete studies involving 2125 COVID-19 patients. Our study demonstrated a significant correlation between vitamin C consumption and death. Vitamin C consumption significantly reduces mortality risk with COVID-19 patients (OR = 0.54, 95% CI = 0.42-0.69, p < 0.00001). Furthermore, there was a link between the severity of COVID-19 and the intake of vitamin C. Patients who consumed vitamin C showed 0.63 times less severity than those who did not take vitamin C (OR = 0.63, 95% CI = 0.43-0.94, p = 0.02). Patients taking vitamin C spent slightly more time in hospital than those who did not take vitamin C (MD = 0.19, 95% CI = -1.57 to 1.96, p = 0.83).

Conclusions: During COVID-19, there was a substantial advantage in taking supplementary vitamin C, at least in terms of severity and mortality.

Keywords: COVID‐19; SARS‐CoV‐2; meta‐analysis; mortality; severity; vitamin C.