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Vitamin D and covid-19

BMJ 2021; 372 doi: (Published 04 March 2021) Cite this as: BMJ 2021;372:n544

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Rapid Response:

Re: Vitamin D and covid-19 - Is it ethical to allow widespread vitamin D deficiency whilst claiming insufficient evidence?

Dear Editor,

In their editorial Vimaleswaran et al call for more research linking vitamin D and Covid-19, despite a significant body of observational and trial data, a sound safety profile, overlapping risk factors for both vitamin D deficiency and severe Covid-19: older age, obesity and darker skin types, as well as higher winter and higher latitudinal prevalence.

In contrast, 220 international physicians, researchers and experts call for action now to improve the vitamin D status for the many vitamin D deficient populations: they signed an open letter in December 2020, stating the size of the vitamin D supplement they themselves take.(2)

Isn’t this the crucial point: advising an adequate effective dose capable to elevate serum 25-hydroxyvitamin D to effective levels for the important well-researched immune modulatory function of vitamin D, more pertinent in a pandemic, rather than for bone health? Not only has the UK guidance to take 400 IU been in existence for a while, but is also not well adhered to, as the authors rightly point out. In addition this small dose is insufficient even for just the bone health of a quarter of people in Scotland (3).

In this pandemic, has the time not come to act on the balance of probabilities, rather than claiming insufficient research in a gate keeping fashion?

(1) Vimaleswaran K S, Forouhi N G, Khunti K. Vitamin D and covid-19 BMJ 2021; 372 :n544 doi:10.1136/bmj.n544
(2) Over 200 Scientists & Doctors Call For Increased Vitamin D Use To Combat COVID-19.
(3) Zgaga L, Theodoratou E, Farrington SM, et al. Diet, environmental factors, and lifestyle underlie the high prevalence of vitamin D deficiency in healthy adults in Scotland, and supplementation reduces the proportion that are severely deficient. J Nutr. 2011;141(8):1535-1542. doi:10.3945/jn.111.140012

Competing interests: No competing interests

09 March 2021
Helga M Rhein
retired general practitioner
previously at Sighthill Health Centre
380 Calder Road Edinburgh EH11 4AU