COVID-19 and Vitamin D

Public Health England re-issued its advice on Vitamin D supplementation to the public on 21st April 2020, via the NHS.uk website which can be found by clicking this link.

In essence, they have extended the “at risk” groups, ie those who should be taking a 10mcg (400 international units, or IU) Vitamin D supplement all year round - not just the winter months - to everyone because of the current lock-down restrictions resulting in everyone spending more time indoors.

Here are some Q and A’s that address some of the issues that are being raised at present, answered by Steve Simbler, one of our pharmacists.

Q: Is there any possibility however that people are getting more exposure to Vitamin D as they are getting out in the middle of the day to get their daily exercise?

A: There's every chance that “outdoor junkies” are getting as much or more exposure to UV compared to usual, but I know from conversations with friends, colleagues and relatives there is a large number of people who are just plain frightened to go out at all, and so are not taking advantage of a daily exercise allowance. In addition, people who might normally spend more time outdoors are having to self-isolate, usually indoors, because other family members have displayed symptoms of Coronavirus.

In addition, there are those considered "vulnerable" who have been written to by the government and who have been advised not to go out at all, others who live in inner city high rise blocks, don't have their own gardens and don't have such easy access to open land or parks. This can result in a vicious cycle in that many are suffering low mood or depression exacerbated by the current COVID-19 threat, and not getting out and topping up their Vitamin D are likely to end up suffering worse symptoms brought about by insufficient Vitamin D.

Furthermore, not everyone is as fortunate in having enjoyed as much sunshine of late as those of us in the south-east of the UK, and so will have had less opportunity to get the benefit of the UVB rays that enable our bodies to produce sufficient Vitamin D in our skin, so bearing in mind Vitamin D's good safety profile, I strongly doubt there is any downside to taking 10mcg (400 IU) a day even through the summer.

An interesting corollary to this is that in my travels and talks with GPs, I find that in almost every case, despite the official recommendation being a daily dose of 400 IU, most GPs themselves are taking 1000 IU per day. This is generally quite safe for most people, but it is worth checking with your local pharmacist if you are taking any regular medication, or have any underlying conditions.

Q: Is there evidence to support the view that this should be the case all year round anyway?

A: Certainly for those following vegetarian or vegan diets, or living in the far north, or even anyone whose work means they are unlikely to get decent sunshine exposure, especially those with darker skin types, there is definitely a case for year-round Vitamin D supplementation.

Q: Is there any evidence to link Vitamin D deficiency with coronavirus?

A: In terms of linking Vitamin D insufficiency with Coronavirus, there have been reports and some early anecdotal research results that support this, but my view is that Vitamin D insufficiency or deficiency is likely to predispose us to any infection, not just Coronavirus in particular, so this is just another very good reason to make sure we do all we can to avoid low Vitamin D blood levels

Q: Is there a connection with higher rate of darker skinned people suffering from COVID-19 and Vitamin D deficiency?

A: I think it is too early to definitively link COVID-19 mortality rates with darker skin types, despite the reports we see in the media, particularly in connection with the apparent ethnic profile of those healthcare workers who have tragically passed away from COVID-19. There will be a massive raft of data that will follow and then there may be some more independent evidence, but until then I think it is prudent to refrain from placing too much reliance in such associations. The mortality profile in the general population will be the indicator of any ethnic links. Similarly there are reports floating around that smokers have been less badly affected by COVID-19, but again we should wait for more robust data to be published.

Q: As a general point, why it is difficult to source enough Vitamin D from food and sunshine, or is a supplement what’s really needed?

A: Firstly, in the UK, from October round to March/April, the elevation of the sun, even on the sunniest of days, is not high enough to allow enough UVB rays to react on our skin to produce Vitamin D. Then when the sun is actually high enough, we are told to cover up with clothing or sun screen to avoid skin cancer, so it is a bit of a no-win situation, despite the message going out (depending on skin type and medical history) that short periods of sunscreen-free exposure is to be encouraged. Also, just walking around we might expose our face and arms, and possibly legs, but maximum UVB absorption is via the torso.

As far as sourcing Vitamin D from our diet, though it is true that Vitamin D is found in some foods, particularly eggs, meat and fish, the amounts are so tiny that our bodies can’t obtain enough to avoid insufficiency or deficiency, and this, coupled with the good safety profile of Vitamin D (as long as it is sourced from a reputable manufacturer) means that regular year-round supplementation is the sensible option.

Steve Simbler

SynBio Vitamin D3 400 IU is an ideal one a day Vitamin D supplement