Vitamin D and COVID-19

13/11/2020

A staggering 49,044 people have lost their lives to Covid-19 in the UK. This figure will continue to rise as we experience the second wave of the pandemic. There has been justifiable excitement this week around the announcement of the Pfizer vaccine. But, while we are waiting for the vaccine roll-out to get underway, is there anything you can do to reduce the risk of either contracting or suffering from severe symptoms of Covid-19. Can taking a daily vitamin supplement do just that? It is entirely understandable that people have been looking to do whatever they can to reduce their risk or COVID-19. 

What Is Vitamin D?

Vitamin D is a fat-soluble vitamin. It is naturally present in a few foods and available as a dietary supplement. It is also produced in our bodies when ultraviolet rays from the sun strike the skin and trigger Vitamin D production.

 
Vitamin D helps regulate the amount of calcium and phosphate in the body. These nutrients maintain the health of keep bones, teeth and muscles. A lack of vitamin D can lead to bone deformities such as rickets in children and osteomalacia in adults.

Can Vitamin D Prevent Respiratory Tract Infections?

There is also a role in Vitamin D in maintaining a healthy immune system. A systematic review and meta-analysis from 2017 in the BMJ drew on data from 25 randomised controlled trials. This was carried out by professor Martineau and his team at the Queen Mary University of London. The trials looked at whether taking a vitamin D supplement could prevent acute respiratory infections.

Can Vitamin D Help Me Reduce The Risk of COVID-19?

Given the relationship found between vitamin D and respiratory infections in 2017, it is not unsurprising that people have suggested a link between vitamin D and COVID-19. There are now close to 30 studies demonstrating that having optimal blood levels of Vitamin D (75-150) reduces Covid-19 risks. This includes a reduced risk of getting the infection, reduced risk of severe disease and reduced risk of dying. Many researchers now regard this evidence as ‘overwhelming.’
However, critics have noted that the trials have either had small numbers of participants or have been open to bias and confounding factors (like past medical history). As such, back in June, the National Institute for Health and Care Excellence (NICE) reported: “there is no evidence to support taking vitamin D supplements to specifically prevent or treat Covid-19.” This was based on data from published studies, all of which they deemed to contain “very low quality of evidence”.

What is the Bottom Line?

Despite the comments of NICE, there is little to be lost from taking Vitamin D supplements daily. Indeed there is potentially a huge amount of gain. We are already advised by NICE to take vitamin D over the winter months or all year round if certain risk factors are present (such as being housebound, or in an institution like a care home, wearing clothes that cover up most of your skin when outdoors or having darker skin pigment). Thus, UK Government advice during the COVID‑19 pandemic is that everyone should consider taking 10 micrograms of vitamin D daily. This can be purchased cheaply over the counter.
 
Scientists in the UK are performing The CORONAVIT trial and will study more than 5000 people. In the meantime, it likely to be of benefit in taking a vitamin D supplement.
 
Dr Emma, GP
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