Good amount of Vitamin D in the body before Covid-19 infection can prevent severe disease and death, according to an international study.
A team from Trinity College in Ireland, University of Edinburgh in Scotland and Zhejiang University in China for the first time looked at both genetically-predicted and vitamin D levels as predicted by ultraviolet B (UVB) radiation -- key for vitamin D production in the skin.
When comparing the two variables, researchers found that correlation with measured vitamin D concentration in the circulation was three-fold stronger for UVB-predicted vitamin D level, compared to genetically-predicted.
The paper, published in the journal Scientific Reports, suggests that vitamin D may protect against severe Covid-19 disease and death.
"Our study supports the recommendation of vitamin D supplementation for not only the maintenance of bone and muscle health during the lockdown, but also the potential benefits in relation to protection from Covid-19," said Dr Xue Li, a researcher on the study from Zhejiang.
"Conducting a properly designed Covid-19 randomised controlled trial of vitamin D supplementation is critical. Until then, given that vitamin D supplements are safe and cheap, it is definitely advisable to take supplements and protect against vitamin D deficiency," added Professor Lina Zgaga, Associate Professor in epidemiology, at Trinity's School of Medicine
Further, ambient UVB radiation at an individual's place of residence preceding Covid-19 infection was found to be strongly and inversely associated with hospitalisation and death.
Previous studies have linked vitamin D deficiency with an increased susceptibility to viral and bacterial respiratory infections. Similarly, several observational studies found a strong correlation between vitamin D deficiency and Covid-19.
A study by researchers from the Azrieli Faculty of Medicine of Bar-Ilan University in Safed and the Galilee Medical Center (GMC) in Nahariya, Israel, showed that people with low vitamin D levels are at least 20 per cent more likely to die from Covid-19 than people who are not.
They found that being deficient in vitamin D before contracting Covid-19 has a direct impact on the disease's severity and mortality.