New research from Trinity College Dublin and the University of Edinburgh examined the association between vitamin D and Covid-19. The results, published in Scientific Reports, found environmental ultraviolet B (UVB) radiation, which is key to the production of vitamin D in the skin, strongly protects against serious illness and death.
Previous studies linked vitamin D deficiency to an increased susceptibility to viral and bacterial respiratory infections. Also, several observational studies found a strong correlation between vitamin D deficiency and Covid-19. However, it could be these effects were confused and were actually the result of other factors; obesity, advanced age or chronic diseases, are also related to a low level of the vitamin.
To overcome this, the researchers were able to calculate the “genetically predicted” vitamin D level. This level is not confounded by other demographic, health and lifestyle factors. Some earlier studies tried but failed to show a causal relationship. This could be because UVB solar radiation, which is the most important source of the vitamin for most people, was ignored.
Analysis from genetics and UVB radiation
For the first time, the researchers jointly analysed the vitamin D level predicted by genetics and UVB radiation. Almost half a million individuals from the UK participated in the study. Environmental UVB radiation prior to Covid-19 infection was assessed individually for each participant.
Researchers found that ambient UVB radiation at home, prior to Covid-19 infection, was inversely associated with hospitalisation and death. This suggests vitamin D may protect against severe Covid-19 illness and death.
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Vitamin D could protect against severe Covid-19
Professor Lina Zgaga, Associate Professor of Epidemiology at Trinity College School of Medicine and lead researcher on the study, stressed the study “adds further evidence that vitamin D could protect against severe Covid-19 infection. It is critical. Conduct a well-designed randomized, controlled trial of vitamin D supplementation for Covid-19. Until then, since these vitamin supplements are safe and inexpensive, it is definitely advisable to take supplements and protect yourself against vitamin D deficiency; especially with winter on the horizon,”she said.
For her part, Professor Evropi Theodoratou, Professor of Cancer Epidemiology and Global Health at the University of Edinburgh and principal investigator of the study, commented, “Given the lack of highly effective therapies against Covid-19, we believe it is important to maintain an open mind to the results of rigorously conducted vitamin D studies. “
Finally, Dr. Xue Li, study investigator from Zhejiang University, “the study supports the recommendation of vitamin D supplementation not only for the maintenance of bone and muscle health during blockage, but also for possible benefits in relation to protection against Covid-19 “.
The results were published in the journal Scientific Reports.