By Dan Iron

Disclaimer: The writer of this article is not a medical doctor and has no medical experience. Nothing in this article should be taken as personal medical advice. It is a call to the Scottish government for action. Professional medical advice should always be sought, especially for people on medication and even more so for people on blood-thinning medication.

I watched a lecture about Covid-19 given by Professor Chris Whitty, Chief Medical Officer for England, at Gresham College in April. It was a very good and comprehensive lecture, about one hour and twenty minutes long, but with one significant omission. There was a lot of detail about general public health issues - washing hands, social distancing, vaccines, possible drugs etc., but there was nothing about what measures individuals could take to improve their own health and thereby improve their chances of avoiding serious disease or death with Covid-19.

At the present moment we don't actually know for certain what personal health measures people can take. There will be so much data arising from the Covid-19 pandemic that it will keep scientists busy for years, if not decades. It seems that people who have better outcomes generally are younger, are not overweight and whose blood pressure and blood sugar are within normal limits.

In addition, there have been several studies announced recently which suggest that levels of vitamin D in blood serum are related to avoidance of serious disease or death from Covid-19. With levels above 75 nmol/l (nanomoles per litre) outcomes are greatly improved. It must be stressed that these studies have largely been produced as pre-prints and have not yet been peer reviewed. It must also be stressed that these studies show a relation between vitamin D levels and outcomes, not cause and effect.

So let's take this information and put it together with what we already know about vitamin D. We know that vitamin D insufficiency is linked to worse outcomes with respiratory diseases, colorectal cancer and bone health. We also know that there are many Scots who have low levels of vitamin D. Edinburgh GP Dr Helga Rhein (, now retired, has been reporting on this for years. However, nothing ever seems to get done about it. Every so often, a newspaper will have a feature on the importance of vitamin D. And then nothing happens. This is something the Scottish Government should be dealing with. The government recommends supplementing with 400 IU per day (International Units, 400 IU = 10 μg (microgrammes), 1,000 IU = 25 μg). To put this in context, I am watching two regular video updates on Covid-19 by front-line professionals. One is taking 2,000 IU per day and the other is taking 2,500 IU per day. Personally I'm taking 3,000 IU per day. But it's the serum level of D (in the form of 25(OH)D) that is the important measure. You have to take a blood test to find this level.

So what is the optimal level of serum vitamin D? To investigate this we can look at two peoples in East Africa still living an ancestral lifestyle - the Maasai and Hadzabe. Their mean levels of vitamin D have been measured to be 119 nmol/l and 109 nmol/l respectively. Does it need to be this high? Probably not. Most of the benefits kick in at a level of 75 nmol/l. My personal strategy is to reach 100 nmol/l by the end of the summer and take a supplement during the winter months. This will ensure that my vitamin D level will be above 75 nmol/l throughout the year. Vitamin D levels always drop in the winter as you cannot get D from sunshine in Scotland between October and March. Vitamin D is stored in fat cells and we all have a tendency to put on weight in the winter months, thereby reducing the amount of vitamin D circulating in the blood. By keeping a high level during the year, we can possibly avoid a second spike of Covid-19 this coming winter. There might also be a benefit in avoiding influenza this coming winter as there is normally an outbreak during the winter months.

We can get vitamin D from food, supplements and sunshine. It is difficult to get enough vitamin D from food. We can get some from oily fish, eggs, liver and so on. The best ways of getting vitamin D are taking supplements and from the action of ultraviolet (UV) B rays on exposed skin. There are possible risks here. Vitamin D makes it easier to assimilate calcium from food. This can lead to problems such as kidney stones. Personally, along with vitamin D I take some vitamin K2 which helps calcium get into the bones, where it belongs. (K vitamins have an effect on blood coagulation so please read the disclaimer at the top of the page.) You also have to make sure your diet contains enough magnesium to balance the calcium (which is a good excuse to eat some dark chocolate). There is also a risk of skin cancer from too much UV light. You have to be sure not to burn your skin. I use the Dminder app (available on iPhone and Android) to let me know what the safe exposure time is.

It is important not to look at the vitamin D issue in isolation. It is important we look at our overall fitness too.

There is also one very important factor which has arisen from the Covid-19 pandemic. According to the Office for National Statistics, in England and Wales BAME people are more than four times more likely to die from Covid-19 than white people. We do not yet have sufficient data from Scotland, but results from the USA show a similar pattern to England and Wales. There are bound to be socio-economic factors at play here but we cannot ignore the fact that people with darker skin take longer in the sun to get vitamin D compared to people with lighter skin. Research in the USA has shown that BAME people have lower serum levels of vitamin D.

The Scottish government should have a plan for this summer for people to get fitter and top up our levels of vitamin D so that we are in better shape to withstand the possible second spike of Covid-19 in the winter. I'd suggest we aim for a serum level of 100 nmol/l by the end of September and take a supplement of 1,000 IU per day in the winter. We need to get everybody tested. This might turn out to be just as important as the Covid-19 antigen or antibody tests. So let's have a fitness programme in our public parks (with social-distancing) led by BAME Scots who can stay in the sun for longer to increase their vitamin D level. Let's call these sessions "D in the Park". We can make sure that "a' the bairns o' Adam" can find D. We can make sure that Black Lives Matter in a tangible, constructive way.