Does Vitamin D levels and its supplementation affect the risk of mortality or ICU admission from COVID-19?

17 Jun 2021

What the research says:

Several systematic reviews have suggested a trend for reduced risk of ICU admission and mortality among patients with COVID-19 infection with high plasma Vitamin D levels. However, the association is not clear and not statistically significant and may be related to other factors including gender and diabetes.

Current clinical guidelines either state there is insufficient evidence to recommend for or against the use of Vitamin D supplementation as an intervention to reduce the risk ICU admission and mortality among patients with COVID-19 or recommend against its use outside of the clinical trial setting.

Nevertheless, considering the plausible chance for clinical benefit, more research is ongoing. There are currently 96 studies listed on that are evaluating the role of Vitamin D in COVID-19 prevention, prognosis and treatment.

What this means for your clinical practice:

  • Advise against preventive high dose Vitamin D supplementation which has not been shown to reduce the risk of infection or more severe COVID-19 disease and may be associated with side effects
  • Advise patients to maintain appropriate levels of Vitamin D through a diverse and nutritionally balanced diet or natural methods such as sunlight on the skin (with appropriate precautions against excess exposure)
  • Vitamin D deficiency, and therefore its supplementation, may be considered according to National evidence and guidance, regardless of the pandemic context.


With grateful thanks to Tiago Maricoto, MD, PhD (Family Doctor, Aradas Health Unit and University of Beira Interior, CACB-Clinical Academic Centre of Beiras, Portugal) for and on behalf of the IPCRG practice driven answers review group.

Resource information

Respiratory conditions
  • COVID-19
Respiratory topics
  • Disease management
  • Treatment - non-drug
Type of resource
IPCRG COVID-19 and respiratory Q&A