Millions of Britons should be encouraged to take vitamin D supplements this winter because they could help fight the coronavirus, according to a report commissioned by the government’s chief scientific adviser.
The scientists’ report said: “It has been suggested that low levels of vitamin D — endemic within the UK, exacerbated by lockdown and which worsen over winter — may contribute to susceptibility to Covid-19 . . . Given the protective effects of vitamin D against respiratory tract infections and wider health benefits, the government should consider how to encourage the use of vitamin D this winter, particularly in vulnerable and low socioeconomic groups.”
Vitamin D deficiency in the UK, at 22%, is higher than in many other European countries and compares with 13.8% in Germany and 12.4% in Ireland. Some Nordic countries, including Sweden and Finland, fortify food such as bread and flour with vitamin D. In America, it has been added to cow’s milk for decades.
Vitamin D is essential for a healthy immune system. People usually make enough of it during summer by being exposed to sunlight. The process takes longer in those with darker skin, which blocks more ultraviolet radiation from the sun. In winter, vitamin D has to come from food, such as eggs, oily fish and mushrooms. It is difficult to eat enough to ingest the recommended dose.
A study cited by the Academy of Medical Sciences, which was published in the British Medical Journal in 2017 and reviewed data from 25 trials, showed vitamin D can help prevent acute respiratory infections, particularly in those with a deficiency.
Adrian Martineau — professor of respiratory infection and immunity at Queen Mary University of London, who led the study — is investigating whether vitamin D could protect against the coronavirus via the national Covidence UK study. In the meantime, its indirect effects will help protect Britons and the NHS. He said: “Anything that is going to stop somebody coming into hospital is going to reduce their risk of catching Covid-19 because we know that’s a potential site of transmission. There’s [also] a chance there could be benefit in terms of immune function, so it’s really a no-brainer to say that this is something that should be promoted.”
Charles Bangham, professor of immunology at Imperial College London and one of the authors of a Royal Society report on the coronavirus and vitamin D, said: “Our work has shown how vitamin D deficiency is more common in several groups most at risk of severe Covid-19, such as the elderly and people from [black and minority ethnic] groups, and has recommended stronger public guidance from the government on preventing deficiency. Preventing vitamin D deficiency may help to prevent severe Covid-19, but the most effective preventive measures are still physical distancing, face coverings and handwashing.”
Public Health England recommends vitamin D pills for those rarely outdoors, living in a care home or wearing clothes covering up most of their skin. People with dark skin should also consider taking supplements frequently.