Saturday 3 October 2020

Covid-19 and VItamin D : compelling evidence from Boston and Tehran

Wharfedale, Yorkshire

Before visiting Boston and Tehran, let us just take a look at the news in the UK and USA during the past few days.

There is quite a lot of scepticism and criticism concerning the clear role of vitamin D in diminishing the impact of Covid-19 in the current pandemic in humankind. Is there a policy form the WHO downwards to suppress information about Vitamin D? We saw false information from the UK Health Secretary Matt Hancock on September 22nd, when he stated in Parliament that "Vitamin D does not appear to have any impact on reducing the incidence of Vitamin D". 

On October 1st it was reported in the UK nation newspapers the The Times, The Mail and Metro that he admitted to this having been a false statement and that the research studies that he referred to did not exist.

There is a difference between the two statements:

"There is no evidence that vitamin D has an impact on Covid-19" and

"There is no evidence that vitamin D supplements have an impact on Covid-19".

The effect of vitamin D can be judged by the blood level of vitamin D and then associated with subsequent Covid-19 infection and deaths from it. It is beyond dispute, as judged by studies from Heidelberg, BariChicago, and others, that low blood levels of vitamin D lead to an unfavourable outcome from Covid-19, possible death.

The benefit of taking a supplement is not quite the same, but the difference is pedantic. With the exception of Matt Hancock, most critics are careful to state that there is not evidence that vitamin D supplements are of benefit, rather than vitamin D.

How does someone living in northern Europe manage to become sufficient in vitamin D (blood level >30ng/ml, 75nmol/L) without taking a supplement? To organise a study of taking a vitamin D supplement takes much longer than testing blood levels. 

But such a study has been undertaken in Spain and the result shows a dramatic benefit. It might be expected that all patients admitted to hospital on account of Covid-19 will now be given vitamin D as a routine. Is this happening? No-one really knows, BUT....

President Donald Trump was admitted to hospital on October 2nd on account of Covid-19, and the statement given by his physician Dr Sean Conley informs us that he is being given Vitamin D, among other treatments. 

Clearly someone highly placed understands and acknowledges, perhaps in secret, the importance of vitamin D.

"Ich weiß, sie tranken heimlich Wein

Und predigten öffentlich Wasser"

Heinrich Heine

"I know they secretly drank wine
And publicly preached water"
My thanks to Karl Pfleger

For wine read "vitamin D". For water read "lockdown and vaccines"

However, there is more evidence available concerning the value of Vitamin D.

Boston University medial Center

For many years Boston has been leading research into vitamin D. The team is headed by Professor Michael Holick, whose activities and commitment are astounding. It was anticipated that good quality research would come out of his department during the pandemic of Covid-19 but of course research is not instantaneous and the research process takes some time. 

The results of the research are now being published, and there are two papers of particular importance.

Covid-19 incidence and blood levels of vitamin D

SARS-CoV-2 positivity rates associated with circulating 25-hydroxyvitamin D levels

This study involved the health records of 191,779 US citizens who were found to be positive for Covid-19, and all of these persons had records of the results of blood levels of vitamin D during the previous 12 months. It was therefore possible to relate a pre-existing blood vitamin D level with subsequent Covid-19 infection.

The results can be summarised as the greater the blood level of vitamin D, the less is the chance of developing Covid-19. Details are shown in the graph.

We can see in this study three important criteria of proof of the causative role of vitamin D deficiency in Covid-19 infection, the criteria having been determined by Sir Austin Bradford Hill

The first is association, there being a clear association between Covid-19 infection and low blood levels of vitamin D.

The second is temporality, as we see that low vitamin D levels pre-dated the Covid-19 infection.

The third is biological gradient, this being shown on the graph. There is a clear gradient of risk of Covid-19 with a varying blood level of vitamin D.

The conclusion is that a a good (sufficient) blood level of vitamin D will reduce by 50% the risk of Covid-19 infection.

The effect of blood vitamin D on serious or fatal Covid-19

Sina Hospital, Tehran

Vitamin D sufficiency, a serum 25- hydroxyvitamin D at least 30 ng/mL reduced risk for adverse clinical outcomes in patients with COVID-19 infection

The second paper concerns the influence of vitamin D on the severity of Covid-19 infection. The study was undertaken in Tehran.

The title of this paper contains the conclusion.

The study was of 611 patients with Covid-19 in the Sina Hospital in Tehran. 

Blood levels of vitamin D (as 25(OH)D) were determined on admission.

A blood level of 30ng/ml or more was regarded as "sufficient".

A blood level of less 30ng is therefore regarded as "insufficient".

The measure of severity of disease was based on the criteria of the US Centre for Disease Control and Prevention (CDC). The paper looks at Severe and  Not Severe.

74% of the 235 patients had severe disease.

Blood vitamin levels (ng/ml) of the total patient group were:

We have seen this in other studies, that the majority of the subjects were deficient in vitamin D. Deficiency of vitamin D is considered to be the most common global health "condition", predisposing to infections. However there is dispute concerning the definition of "deficiency" of vitamin D. 

In the present study the term "deficiency" is not used. Equal to or greater than 30ng/ml (75nmol/L) is said to be "sufficient".

We can see worse health, a higher incidence of the need for  ICU admission, more severe illness, low oxygen levels, and loss of consciousness in those with the lower blood levels of vitamin D.

It is obviously a great advantage to have a good blood level of vitamin D (30ng/ml (75nmol/L) or greater) when admitted to hospital on account of Covid-19 infection.


In this study no-one under the age of 40 died.

16.3% of those aged 40 or older died.

Death was related to vitamin D status. 90.3% of those who died had a blood vitamin D level less than 30ng/ml (75nmol/L). Only 9.7% of those who died had blood level of 30ng/ml of greater. 

The presence of a higher sufficient level of vitamin D in the blood was associated with a reduction of deaths from about 90% to 10% percent, an absolute reduction of 80%. Another way of expressing it tis that deaths were 9 times higher in those with low levels of vitamin D.

This is remarkable finding, the obvious benefit of a sufficient blood level of vitamin D, 30ng/ml (75nmol/L) or greater, in the prevention of death from Covid-19.  

This is remarkable finding of the benefits of a sufficient blood level of vitamin D. It conforms to the findings of previous studies and it must not be ignored.

Vitamin D deficiency and Covid-19 : its vital importance in a world pandemic




  1. Vitamin D is an essential hormone for our survival. Hunter-gathers and life-guards in swimming pools and in beached have an average serum 25(OH)D of 46 ng/mL, seems the optimal physiological concertation.
    In routine clinical practice doses between 2,000 and 5,000 IU/day is a reasonable a longer-term dose to maintain healthy blood levels in most people. However, there are exceptions, as some needs much higher daily disease. Common sense approaches are needed. Emerging COVID-19 data strongly support benefits from vitamin D sufficiency.

    Myths & Facts: Staying Healthy During COVID-19 Pandemic
    The common link to the U-Tube channel o COVID-19:

    However, in emergency situations, such as to prevent complications or following exposure to COVID-19, 4,000 IU/day would not touch, those who are vitamin D deficient. They do need up front-loading doses such as, 50,000 daily for few days 100,000 IU daily for five days, or 400,000 IU stat dose, etc. (many possibilities), to rapidly built-up vitamin D stored and maintain serum 25(OH)D concentrations in excess of 30 ng/mL; preferably more than 40 ng/L to obtain the full immune protection.
    There are a few publications regarding this in the following ResearchGate website:

    Vitamin D is the quickest and most important way to boost the innate immune system allowing to overcome COVID-19. It will however not prevent getting the infections but control complications and markedly reduce deaths. Other health interventions have minor help. Some still recommend, 400 to 800 IU/day which is worthless is the current situation. Myths & Facts: Staying Healthy During COVID-19 Pandemic.
    The common link to the U-Tube channel o COVID-19:

    Please feel free to subscribe to above (free) and forward the links to others for their benefit, especially watch the video #57 (RAS presentation). These are complementary to the discussions of Dr Grime
    Thank you.
    Dr. Sunil Wimalawansa, MD, PhD, MBA, DSc.
    Professor of Medicine Endocrinology & Nutrition

  2. Hello Dr Grimes- could you tell me whether the UK level for sufficiency is still set at 20ng/l or if it has been raised to 30ng/l recently?

  3. We have learned a great deal about vitamin D and immunity during this pandemic, but it will take a long time for this to be translated into official documents. It is clear that if you want to avoid rickets/osteomalacia the blood level should not be below 10ng/ml, and between 10 and 20ng/ml. But is is now clear that if you want to maximise immunity the blood level should be above 30ng/ml, between 30 and 40ng/ml. We should work on personal blood levels and targets, like we do with glucose and blood pressure etc. This is definite but not yet in official documents.

  4. Thank you. I frequent a Health unlocked patient forum for atrial fibrillation and have been trying to persuade fellow forum members that the best way to protect themselves againt covid is to test their vit D status and up their vit D if deficient. I live in France where the sufficiency level starts at 30ng/mL and am having difficulty in convincing those who have been tested and told their levels are ok that they have been misled because the standards in the UK are lower for sufficiency, insufficiency and deficiency. I myself am prescribed Calcifediol drops and have a level between 45 and 60 ng/mL so I am lucky to have such a good GP!

    1. Thanks Madge - atrial fibrillation is associated with inflammation and a good way to reduce this is Vitamin D. Also have occasional AF, and an increased dose of vitamin D seems to have helped.

    2. Thanks -I did not know that. I have high levels of inflammation as I suffer from Fluoroquinolone Toxicity. My first afib attack was after my last floxing 5 years ago. I am sure that my health would be even worse if I did not maintain a high level of vit D. When my deficiency was diagnosed in 2007 I had had a tendonitis in my thigh that had been causing lots of pain and a severe limp for several months. My GP prescribed a loading dose ampoule and within 3 days I was walking normally and the pain had disappeared. So you can see how I became a fan of vit D and started to research it's benefits! I have encouraged my family to take it. Anecdotally I sent my daughter a spare bottle of Calcifediol drops in March. She and her house mate caught covid. They said that after taking a loading dose of 10 drops each and then 3 drops daily they started to feel much better. This is a much lower dose than was given in the Reina Sofia trial but they are young and healthy.

  5. I was delighted to see that Rupa Haq, MP for Ealing Central and Acton, wrote a Thunderer article in the Times of 7th October endorsing your views about Vitamin D and Covid. Keep up the good work.

  6. Interesting findings.
    Need to supplement vitD seem worth while.
    No harm