Effects of Vitamin D Supplementation on COVID-19 Related Outcomes: A Systematic Review and Meta-Analysis
Hosseini et al.
, Effects of Vitamin D Supplementation on COVID-19 Related Outcomes: A Systematic Review and Meta-Analysis
, Nutrients, doi:10.3390/nu14102134 (meta analysis)
Systematic review and meta analysis showing significantly lower ICU admission and mortality with vitamin D treatment. There was no significant difference for cases.
Currently there are 107 vitamin D studies
and meta analysis shows:
risk of death, 54.0% lower, RR 0.46, p < 0.001.
risk of ICU admission, 65.0% lower, RR 0.35, p < 0.001.
risk of case, 9.0% lower, RR 0.91, p = 0.11.
Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates
Hosseini et al., 20 May 2022, peer-reviewed, 3 authors.
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Effects of Vitamin D Supplementation on COVID-19 Related
Outcomes: A Systematic Review and Meta-Analysis
Banafsheh Hosseini 1,2, *, Asmae El Abd 1 and Francine M. Ducharme 1,2,3
Citation: Hosseini, B.; El Abd, A.;
Ducharme, F.M. Effects of Vitamin D
Supplementation on COVID-19
Related Outcomes: A Systematic
Review and Meta-Analysis. Nutrients
Clinical Research and Knowledge Transfer Unit on Childhood Asthma, Research Centre, Sainte-Justine
University Health Centre, Montreal, QC H3T 1C5, Canada; firstname.lastname@example.org (A.E.A.);
Department of Pediatrics, Faculty of Medicine, University of Montreal, Sainte-Justine Hospital,
Montreal, QC H3C 3J7, Canada
Department of Social and Preventive Medicine, Public Health School, University of Montreal,
Montreal, QC H3N 1X9, Canada
Abstract: The COVID-19 outbreak has rapidly expanded to a global pandemic; however, our knowledge is limited with regards to the protective factors against this infection. The aim of this systematic
literature review and meta-analysis was to evaluate the impact of vitamin D supplementation on
COVID-19 related outcomes. A systematic search of relevant papers published until January 2022
was conducted to identify randomized controlled trials (RCTs) and non-randomized studies of
intervention (NRISs). The primary outcomes included the risk of COVID-19 infection (primary prevention studies on uninfected individuals), hospital admission (secondary prevention studies on mild
COVID-19 cases), and ICU admission and mortality rate (tertiary prevention studies on hospitalized
COVID-19 patients). We identified five studies (one RCT, four NRISs) on primary prevention, with
five (two RCTs, three NRISs) on secondary prevention, and 13 (six RCTs, seven NRISs) on tertiary
prevention. Pooled analysis showed no significant effect on the risk of COVID-19 infection. No
meta-analysis was possible on hospitalization risk due to paucity of data. Vitamin D supplementation
was significantly associated with a reduced risk of ICU admission (RR = 0.35, 95% CI: 0.20, 0.62)
and mortality (RR = 0.46, 95% CI: 0.30, 0.70). Vitamin D supplementation had no significant impact
on the risk of COVID-19 infection, whereas it showed protective effects against mortality and ICU
admission in COVID-19 patients.
2022, 14, 2134. https://doi.org/
Keywords: vitamin D; COVID-19; hospitalization; mortality; ICU admission
Academic Editor: Bruce W. Hollis
Received: 20 April 2022
Accepted: 13 May 2022
Published: 20 May 2022
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