You may have heard of the important role of vitamin D in people who have Coronavirus – but how much do we really know at the early stage of the virus?
What is Vitamin D?
Often known as ‘the sunshine vitamin’, vitamin D is actually a vitamin and a hormone, which can be made in the body.1 Vitamin D regulates the amount of other important minerals in our body such as calcium and phosphate, both needed for healthy bones, teeth and muscles.
Vitamin D & Diet
There are two major forms of vitamin D which are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). The main sources of vitamin D are sunlight exposure (where it is synthesised in the skin) and foods or dietary supplements. Between the months of April and September, skin synthesis is the main source of vitamin D for most people.2 Vitamin D is found in modest amounts in some foods;
– Oily fish such a salmon, sardines and pilchards contain reasonable amounts.
– Red meat
– Egg yolks, meat and offal contain modest amounts but this can vary throughout the seasons
Vitamin D and Coronavirus
We know that individuals with diabetes are at higher risk of infections, especially pneumonia and influenza and that people living with obesity (who have a body mass index (BMI) of greater than 40kg/m2) as well as those 70 years old and above should be shielding and staying home as much as possible.2
A recent study concluded that attention to nutrition and protein intake is important for individuals with diabetes in times of COVID-19 and also that deficiencies of vitamins need to be corrected.3
Public health England guidelines state that the following groups are at risk of vitamin D deficiency and should take a 10 microgram supplement of vitamin D all year around:3
- People in institutions such as care homes
- People who always cover their skin when outside
- People whose skin has little or no exposure to the sun
Higher dose Vitamin D?
A recent Irish study led by Professor Rose Anne Kenny published in the Irish Medical Journal called for immediate higher vitamin D supplementation for those in hospital, in nursing homes or those who are older.4
Prof Kenny said: “Though we do not know specifically of the role of vitamin D in Covid-19 infections, given its wider implications for improving immune responses and clear evidence for bone and muscle health, those cocooning and other at-risk cohorts should ensure they have an adequate intake of vitamin D.”
Another group of researchers from the US have recommended a very high does of vitamin D for the first few weeks of infection (10,000IU/day), however, the team acknowledge the limitations of the study and say that further research is required before suggesting these very high supplementation levels for the general public.5
One more recent study had suggested that those with vitamin D deficiency may be more prone to infection (specifically respiratory infections) from the Coronavirus and that vitamin D could work as a therapeutic option for treatment of the virus. It is important to note this is a very early recommendation and based on bovine studies, therefore cannot be translated to humans yet.6
It should be noted that an expert panel in the UK 2016 Vitamin D report evaluated the evidence and did not find strong enough evidence to support recommending vitamin D supplements to reduce the risk of respiratory tract infections.
Should I supplement?
If you are shielding and not getting sunlight, the government recommendation is that you should take an over the counter vitamin D supplement of 10 micrograms every day. If you have had very low vitamin D in the past, you may need a higher dose – speak to your pharmacist or doctor for advice on this.
As for the higher doses of vitamin D specifically to prevent or treat Coronavirus, the evidence so far is very limited and higher dose recommendations cannot be made yet. If you are unsure or want to take a higher dose then you should discuss this with your doctor or pharmacist.
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