Vitamin D : an invaluable anti covid aid

“Vitamin D could be of invaluable help in the fight against COVID 19,” says Dr. Jean-Michel Wendling, an occupational health prevention specialist in Strasbourg, France, a consultant for

Dr Jean-Michel- wendling
Dr Jean-Michel- wendling

By Jean-Michel Wendling

A French team including researchers and clinicians from Marseille, Angers and Saint Etienne are at the forefront. Jean-Marc Sabatier (research director at the CNRS in Marseille) and Cédric Annweiler (head of the geriatric service at the CHU in Angers) have published two fine studies on retirement homes and geriatric services.

These works were published in November. In a retirement home, a first study was launched on sixty-six residents with COVID-19, involving patients “recharged with vitamin D3” who were compared to a “control group” without treatment. The treated (n = 57) and control (n = 9) groups were comparable in age, as was the severity of COVID-19 and the use of associated COVID-19 medications. All patients were followed for 36 days. Follow-up results showed that 82.5% of participants in the treated group survived COVID-19, compared to only 44.4% in the untreated group (p = 0.023). The relative risk of mortality was reduced by 89% in the group treated with vitamin D3 supplementation (ORa = 0.11; p = 0.003). The authors conclude that vitamin D3 bolus supplementation during or just prior to COVID-19 was associated in frail elderly people with less severe COVID-19 and better survival. (1).

This study was complemented by monitoring the effect of geriatric inpatient treatment on 3 groups. In the group regularly supplemented with vitamin D, 93.1% of patients with COVID-19 survived to day 14 and 81.2% in the group of patients recharged at the time of diagnosis. The untreated group had higher mortality and 68.7% survived. (2)

Curative treatment in “controlled trials” very promising abroad too!

An Indian team conducted a study on 40 SARS-CoV-2 RNA-positive individuals who were randomly selected and divided into two groups: those treated (n = 16) and controls (n = 24). Baseline blood levels of 25 (OH) D were considered similar between the two groups respectively.

The number of subjects who failed their test after taking vitamin D was higher in the treated group: 62.5% of patients versus only 20.8% in the control group (p <0.018). Fibrinogen levels also decreased significantly with cholecalciferol supplementation (intergroup difference 0.70 ng/ml; P = 0.007). (3)

In a 76-patient controlled trial study conducted by the Respirology Department of the Reina Sofía University Hospital in Córdoba, Spain, patients were selected by electronic randomization on the day of admission to take (n=50) or not (n=26) oral calcifediol (0.532 mg oral calcifediol (0.266 mg) on days 3 and 7 and weekly thereafter until discharge or admission to the intensive care unit).

In the calcifediol-treated group, only 2% were admitted to the Intensive Care Unit, while out of 26 untreated patients, 13 were admitted (50%) ( p <0.001). The risk is reduced by 97% according to the authors. (OR = 0.03). None of the treated patients died and all left without complications. Of the 13 untreated patients, two died. These results need to be extended to larger patient series but are very promising. (4)

These very promising results need to be confirmed by more clinical observations.

In Europe too

Some European states are taking the lead and launching initiatives


English ministers develop massive supplementation plan for nursing home residents and clinically extremely vulnerable people in England

Elderly and vulnerable people will be treated with vitamin D for four months starting in December in the United Kingdom, announced UK Secretary of State for Health and Social Care Matt Hancock on November 7. Beneficiaries include immunocompromised people, cancer patients, or those with severe respiratory conditions. “We will ensure that those most in need of vitamin D will have a stockpile to last them through the winter. A number of studies suggest that vitamin D supplementation could have a positive impact on people suffering from Covid-19,” explains a source close to the Ministry.


In Norway, researchers have launched a clinical study to determine whether cod liver oil, rich in vitamin D, could have beneficial effects on Covid-19, details Le Monde. The decision was taken following a major survey launched in March at Oslo hospital during which 150,000 people, including 2,000 who were positive for the virus, answered a questionnaire. Their answers show that regular consumers of cod liver oil are, in a significant proportion, less often contaminated and become less seriously ill if they are infected.

The opinion of the Academy of Medicine: 22 May 2020

The National Academy of Medicine gave its recommendations in its publication of May 22. “Vitamin D modulates the functioning of the immune system by stimulating macrophages and dendritic cells and plays a role in regulating and suppressing the cytokine inflammatory response that causes the acute respiratory distress syndrome that characterizes the severe and often lethal forms of Covid-19”.

At that time, she recommended and estimated :

  • that the administration of vitamin D by the oral route is a simple, inexpensive measure and reimbursed by the Assurance Maladie ;
  • the need to ensure vitamin D supplementation in the French population in a report in 2012,
  • to rapidly measure serum vitamin D levels (i.e. 25 OHD) in people over 60 years of age with Covid-19, and to administer a loading dose of 50,000 to 100,000 IU in case of deficiency, which could help limit respiratory complications,
  • to provide vitamin D supplementation of 800-1000 IU/day in persons under 60 years of age upon confirmation of Covid-19 diagnosis.

To date, apart from these recommendations, there is no need to go to the pharmacy for a vitamin!

To have sufficient intakes it is desirable to expose oneself to light and sunlight “face and arms” during 30 minutes per day, by practicing, at best, a physical activity for example and by having a diversified diet including very regularly fatty fish and dairy products.

Taking larger doses is the responsibility of the attending physician who will judge the need to supplement according to the geographical location and lifestyle.

  1. Cédric Annweiler, Bérangère Hanotte, Claire Grandin de l’Eprevier, Jean-Marc Sabatier, Ludovic Lafaie, Thomas Célarier, Vitamin D and survival in COVID-19 patients: A quasi-experimental study, The Journal of Steroid Biochemistry and Molecular Biology, Volume 204, 2020, 105771,ISSN 0960-0760,
  2. Annweiler, G.; Corvaisier, M.; Gautier, J.; Dubée, V.; Legrand, E.; Sacco, G.; Annweiler, C., On behalf of the GERIA-COVID study group; Vitamin D Supplementation Associated to Better Survival in Hospitalized Frail Elderly COVID-19 Patients: The GERIA-COVID Quasi-Experimental Study. Nutrients 2020, 12, 3377.
  3. Rastogi A, Bhansali A, Khare N, et al Short term, high-dose vitamin D supplementation for COVID-19 disease: a randomised, placebo-controlled, study
  4. Entrenas Castillo M et al. Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study ». J Steroid Biochem Mol Biol. 2020 Oct;203:105751. doi: 10.1016/j.jsbmb.2020.105751. Epub 2020 Aug 29. PMID: 32871238; PMCID: PMC7456194.
  5.  (SHADE study) Postgraduate Medical Journal Published Online First: 12 November 2020. doi: 10.1136/postgradmedj-2020-139065