The government has ordered an urgent review of the potential ability of vitamin D to reduce the risk of coronavirus.
It comes amid growing concern over the disproportionate number of black, Asian and minority ethnic people (BAME) contracting and dying from the disease, including a reported 94% of all doctors killed by the virus.
A delayed Public Health England review into the reasons why BAME people are disproportionately affected which pointed to historical racism was said not to have yet reviewed the role of diet and vitamin D.
The Scientific Advisory Committee on Nutrition (SACN) was ordered to do this work last month and consider recent evidence on vitamin D and acute respiratory tract infection in the general population.
In a parallel development, the National Institute for Health and Care Excellence (Nice) is conducting a “rapid” evidence review on vitamin D “in the context of Covid-19” with support from Public Health England. It is understood the reviews will be published in the coming weeks.
Public Health Scotland and NHS boards are also assessing emerging evidence to see if the so-called sunshine nutrient should be prescribed in hospitals and to high-risk groups to mitigate a second wave of Covid-19.
Adrian Martineau, a professor of respiratory infection and immunity at Queen Mary University of London, welcomed the reviews and said deaths among BAME NHS staff had brought the question of vitamin D deficiency to the fore.
“Vitamin D could almost be thought of as a designer drug for helping the body to handle viral respiratory infections,” he said. “It boosts the ability of cells to kill and resist viruses and simultaneously dampens down harmful inflammation, which is one of the big problems with Covid.”
He is currently leading a national study collecting information about risk factors for Covid-19 with a focus on vitamin D deficiency to address the absence of research in this area. Any UK resident aged above 16 is eligible to participate.
“There are no clinical trials of vitamin D to prevent Covid ongoing anywhere in the world to my knowledge and clinical evidence for its use to reduce risk of acute respiratory infections is mixed.”
However, studies have suggested that vitamin D supplementation is safe and protects against acute respiratory tract infection. Higher levels of melanin in the skin lead to lower levels of vitamin D absorption which are exacerbated in colder countries which see less sunlight. This can cause immune systems to be weaker.
NHS England has acknowledged reports about vitamin D potentially reducing the risk of coronavirus but has said there is currently not enough evidence to support this.
It currently advises people to consider taking 10 micrograms of vitamin D a day to maintain bone and muscle health because they may not be getting enough sunlight if indoors most of the day. There is heightened concern over lack of exposure to sunlight during the lockdown.
Current UK vitamin D advice is focused on musculoskeletal health conditions such as rickets and there are fears that its effect on general immune systems has been overlooked. On 3 June the Scottish government specifically recommended people from minority ethnic groups with dark skin to take the supplement.
Across the UK, as many as 750 frontline NHS staff have received free immune support packs including liposomal vitamin C, vitamin D and zinc from a voluntary initiative, and there has been some frustration that a more holistic approach to the pandemic has not been implemented.
Singapore general hospital reportedly routinely gives coronavirus patients aged over 50 a mix of vitamin D, magnesium and vitamin B12, while countries which have recently had summers have generally been less affected by the pandemic.