Covid-19, Vitamin D, Ethnicity – and official inaction

Covid-19, Vitamin D, Ethnicity and official inaction

Garden during lockdown

During the UK lockdown and the delightful weather that accompanied it, I have spent much time in the garden, and  I remembered research that I undertook in 1990. It was part of investigation into determining the reasons why socio-economic disadvantage and Asian ethnicity might be associated with illness and reduced life-expectancy, especially in the north-west of England. The investigation concluded that the key to this problem (and it still exists) is reduced exposure to the sun and thereby low vitamin D levels in the body. A small part of the investigation was a short study of whether the ownership of a garden would influence blood levels of vitamin D.

Figure 1. Vitamin D levels determined by housing type and season

There is a difference as can be seen in Figure 1. People living in a house with a garden have on average a higher blood vitamin D level than those without a garden, in summer and in winter. Note that the averages were all below the ideal level of 30ng/ml. People whose houses do not have gardens are likely to be relatively socio-economically disadvantaged, and as we can see deficient in vitamin D. This should be officially recognised.

The study shows something else. Blood levels of vitamin D are higher in the summer than in the winter, as has been demonstrated on many occasions. This explains "winter flu", more deaths in the winter than in the summer, and perhaps why at present Covid-19 is worse in the northern hemisphere where we have been emerging from our winter than in the southern hemisphere, where the summer is just at an end. When we experience winter flu, it is not that the virus by some unnatural miracle "wakes up", it is that our immunity "goes to sleep" because of less vitamin D.

We now have the experience of Covid-19 in hospitals in south-east Asia, and their research that has demonstrated clearly the important protective action of vitamin D.

Indonesia

A new study has recorded blood levels of vitamin D in 780 hospital patients with Covid-19. Almost half of them died, and although Indonesia is very close to the equator, more than half of the 780 were deficient in vitamin D (blood levels less than 30ng/ml).

Figure 2. Outcome of Covid-19 related to vitamin D status

We can see in Figure 2 that of the 388 patients with blood levels of vitamin D greater than 30ng, only 16 died, but of the 179 with lowest levels of vitamin D, less than 20ng/ml, 177 died. Blood level of vitamin D was an extremely powerful predictor of either survival or death. 

I wonder how many Covid-19 patients in the UK have had blood levels of vitamin D tested.

Philippines

Figure 3. Severity of Covid-19 related to vitamin D status

I have described this study in a previous post. I have displayed in Figure 3 numbers rather than percentages. 55 out of 212 patients had blood vitamin D levels greater than the ideal minimum of 30ng/ml. Of these 55, 47 had mild disease, and the disease was moderate in 4, serious in 2, and critical in 2. Only 2 patients with low blood levels of vitamin D had mild disease and 155 had moderate, severe, or critical disease. Patients who had died were not included in this study.  

The message

Look at results: based on three categories of blood levels of vitamin D, which category would you choose to be in? I would choose greater 30ng/ml. It is very clear that if you want a Covid-19 illness to be only mild, make certain that you have plenty of vitamin D in your body.

I would certainly not want my blood level to be less than 30, as if I catch Covid-19 I would want the illness to be mild, rather than moderate, serious, critical or fatal.

There has been some controversy in the past as to what the ideal blood level of vitamin D should be. It should be based on its relationship to disease, and it is quite clear from these two studies using Covid-19 as a model that the ideal blood level of vitamin D is greater than 30ng/ml (=75nmol/L).

I am pleased to report that last time my blood level of vitamin was measured, about two years ago, it was about 38ng/ml. It is unusual to have such a level unless eating fish for every meal, having a great deal of sun or UV exposure, and of course taking a supplement of vitamin D3. If taking a supplement it needs to be in a dose of about 2,000 units (= 50mcg) each day, or perhaps twice this during the present pandemic. Recommended doses of 400 units (10mcg) will not achieve a target blood level of 30, unless accompanied by a lot of fish or UV light.

The importance of vitamin D in immunity

Vitamin D is essential for maximum immunity as well as muscle-skeletal health, as I have pointed out in previous posts. The “immunity” of an individual cannot be measured directly, although critical illness or death from Covid-19 will give a good indication of low immunity. To assess immunity when not desperately ill, the best test would be the blood level of vitamin D.

The medical and scientific advisors to the government cannot be ignorant of the immune-enhancing effects of vitamin D and the need to keep the blood level above 30ng/ml to achieve maximum immunity. The information has been published in a variety of medical journals, mainly since 1983.

They should know that vitamin D is created by a non-enzymatic photochemical reaction, the direct effect of the sun on the steroid precursor 7-dehydro-cholesterol (7-DHC). This first occurred 1.2 billion years ago in plankton in the oceans. It was an important accident because the synthesis of vitamin D absorbs UV energy from the sun, thereby reducing tissue damage from UV energy. This is important in humankind today, and for example we find that melanoma is less severe in people who have generated a good blood level of vitamin D.

Evolution since 500 million years ago led to the double activation of vitamin D in the liver and kidneys, and it then became a hormone with biological functions. This function is the activation of an enzyme in the cell wall, the vitamin D receptor (VDR), which also had to evolve. Vitamin D in its activated form 1,25-(OH)D (calcitriol) combines with VDR, forming a hetero-dimer, what is called a ligand. This acts within target cells (including immune cells) and in turn activates specific genes. This process will switch on the amplification of the defensive immune process in response to infection. 

Ethnic variations

Previous posts have indicated the undue burden of the black African and Asian communities of the UK during the pandemic of Covid-19. This must be known to the network of scientific advisors, but why do they keep quiet? The government, or the public health bodies of the nations of the UK, are not releasing information concerning those who have died from Covid-19, unlike the health service of Italy which released good quality useful information. The UK government does not officially accept that black African and Asian ethnicity is a strong risk factor for the need of ventilatory support and death from Covid-19. 

In parliament last week the acting prime minister did not know the number of health service staff who had died from Covid-19. There has been no government comment on the fact that so far 23 out of 24 doctors who have died from Covid-19, were of black African or Asian ethnicity. The usual explanation of the excess deaths in ethnic minorities is socio-economic disadvantage, but the paradox of the doctors’ deaths  invalidates this. The explanation is not sociological: it is biological, vitamin D deficiency resulting from skin pigmentation and sun-avoiding behaviour.

The medical and scientific advisors to the government must be aware of this. But why silence? Why the refusal even to discuss it? We might expect that news reporters or politicians are not aware of the science of vitamin D, but some of the network of scientific advisors must know the published details.

Why no action?

During the present pandemic of Covid-19 the UK government is being advised by its Scientific Advisory Group for Emergencies (SAGE), but generally the government receives its nutritional advice from the Scientific Advisory Committee for Nutrition (SACN). Vitamin D is considered to be part of nutrition, and so SACN has, or had, a Vitamin D Working Group. It produced its 289 page report in 2016 and it was subsequently disbanded. 

The report provides a major review of the metabolism and function of vitamin D (it uses units of nmol/L and mcg doses, but I will show both). It emphasises the importance of vitamin D in musculoskeletal health.  It states that the blood level of vitamin D should not be below 10ng/ml (=25nmol/L). It states that when a vitamin D supplement is necessary, usually in pregnancy, a dose of 10mcg (400units) is safe and adequate. However it also states that it is only adequate to achieve this minimal blood level of 10ng/ml (=25nmol/L). It can be seen from the Philippine and Indonesian studies that this minimal blood level would condemn many Covid-19 patients to intensive care and possible death.

The report (now engraved in stone with no review planned) identifies a role of vitamin D in immunity but comes to no conclusion as to its usefulness. When sitting in a committee there is no necessity for speculation, and demands for "proof" can be very rigorous. Most people do not realise that proof is pragmatic, and it can change with time and circumstances. As I indicated in previous post, Sir Austin Bradford Hill in his "criteria", regards careful observation as the basis of proof when experimentation is not always possible. The acceptance that cigarette smoking causes lung cancer was based on observation (of doctors) rather than experimentation. 

And so it is with vitamin D. The studies from Indonesia and the Philippines are observational, but the observations are powerful. It is up to individuals to make their own decisions. We might decide not to smoke cigarettes, and in this we are encouraged by the government. On the basis of similar observations (and with a strong scientific basis) we might decide to take a vitamin D supplement, but at this time of national emergency the government is providing no encouragement.

The government will not go beyond the SACN report, and its advisors always refer to it. Knowledge is officially “complete”, but in reality it is incomplete. The government, and therefore the nation at this time of more than 26,000 deaths from Covid-19, is stuck with a poor quality approach to vitamin D, which holds so much potential.

The pandemic also provides a unique opportunity for clinical research into vitamin D. However if I were asked to be recruited into a clinical trial of vitamin D I would say "Yes, as long as I receive vitamin D and not the placebo". In practice I would not be accepted for such a trial as I already take a vitamin D supplement. If a vitamin D trial is conducted with the participants giving  true informed consent, I cannot foresee the trial taking place. The evidence of life-saving benefit is now so great that to accept a placebo on entry to hospital with Covid-19  could be regarded as attempted suicide, given the one third mortality risk.

In the meantime we each need to make a pragmatic decision, assuming that we have been given the necessary information, and that is only rarely the case. What is to been gained  by taking a vitamin D supplement? The answer is a much reduced risk of needing intensive care or dying. What is to be lost? Perhaps dying or requiring intensive care, but nothing else. Taking vitamin D 100,000 units as just a single dose will do no harm and will cost approximately £1. 

The studies from Indonesia and the Philippines are powerful indicators of the benefits of vitamin D, which does not actually prevent Covid-19 infection, but it prevents serious disease and death. This is new information that should be regarded as a "game changer". We must absorb this new information and incorporate it into action.

The great economist John Maynard Keynes stated: “When the facts change, I change my mind - what do you do, sir?”  The answer from the government at present is “Nothing”.