Vitamin D and Covid-19 By Mrs Vera West


          It has been noticed that vitamin D deficiency has occurred in a statistically significant number of Covid-19 patients, suggesting that this vitamin could provide a key in dealing with infections in vulnerable patients:


“More than 80 per cent of COVID-19 patients at a hospital in Spain had a vitamin D deficiency, according to a new study.

Researchers at the University Hospital Marques de Valdecilla in Santander, Spain looked at the vitamin D levels of 216 patients admitted to hospital for coronavirus treatment between March 10 and March 31.

For the study, the 216 hospitalized patients’ vitamin D levels were compared to those of a control group of 197 people of similar age and sex from a population-based cohort in the same geographical area.

Of the 216 hospitalized patients, 19 who had been taking oral vitamin D supplements for more than three months before their admissions were analyzed as a separate group.

The researchers found that 82 per cent of the hospitalized COVID-19 patients (who were not taking supplements) were vitamin D deficient, while 47 per cent of the control group had the same deficiency.

The study also noted that vitamin D levels were “especially lower” in men with COVID-19 compared to women.

Dr. Jose Hernandez, a co-author of the study and an associate professor of neurophysiology at the University of Cantabria in Spain, said there are many factors that could explain why men with COVID-19 had lower vitamin D levels than women, including lifestyle or dietary habits and different comorbidities.

The study’s authors were particularly interested in studying vitamin D because they said there’s evidence to suggest it plays a role in COVID-19 infection. Vitamin D is a hormone produced by the kidneys, which controls blood calcium concentration and affects the function of the immune system.

Vitamin D deficiency has also been linked to health concerns including heart disease, diabetes, cancer, and multiple sclerosis.

According to the study, there is also “compelling evidence” for an epidemiological association between low levels of vitamin D and infections such as influenza, HIV, and the hepatitis C virus.

“There are numerous pieces of evidence in the literature that support the beneficial effect of vitamin D on the immune system, especially regarding protection against infections, including viral infections,” Hernandez said in an email to on Sunday.

While the researchers reported a higher prevalence of vitamin D deficiency in hospitalized COVID-19 patients compared to the control group, they did not find an association between vitamin D levels and the severity of the disease, such as the need for ICU admission, mechanical ventilation, or even death.

And, although they didn’t establish an association between vitamin D deficiency and the severity of COVID-19, the study’s authors noted that the group of hospitalized patients who had been taking oral supplements prior to admission had slightly more favourable outcomes than those who didn’t take supplements before they were admitted to hospital, including lower ferritin levels, a decreased need for the immunosuppressive drug tocilizumab, and lower ICU admissions.

The study found that patients with a vitamin D deficiency also had raised serum levels of inflammatory markers, such as ferritin and D-dimer.

“The most severe forms of COVID-19 are characterized by a hyperinflammatory state, the so-called ‘cytokine storm,’ that occurs over the first week of symptoms’ onset, and led to acute respiratory distress syndrome and other organ complications causing increased mortality,” Hernandez explained.

“We found that COVID-19 patients with lower serum vitamin D levels had raised serum ferritin and D-dimer levels, which are markers of this hyperinflammatory response.”

In addition to not establishing a relationship between low levels of vitamin D and the severity of COVID-19, including mortality, the study’s authors also acknowledged their research doesn’t show that vitamin D deficiency is a risk factor for contracting the disease.

“We must wait for the results of the ongoing large and properly designed studies to determine whether vitamin D can prevent SARS-COV-2 infection, or reduce its severity,” Hernandez said.

Given the safety and low cost of vitamin D treatments, Hernandez said it would be reasonable to treat those who are most at risk of vitamin D deficiency, such as seniors and those with comorbidities, and who also happen to be the most at risk for developing severe outcomes from COVID-19.”


These vitamin D3 studies of Covid-19, have led to UK authorities advocating fortification of bread and milk with vitamin D3 to aid in preventing Covid-19, or diminish its effects:


“Scientists are calling for ministers to add vitamin D to common foods such as bread and milk to help the fight against Covid-19.

Up to half the UK population has a vitamin D deficiency, and government guidance that people should take supplements is not working, according to a group convened by Dr Gareth Davies, a medical physics researcher.

Low levels of vitamin D, which our bodies produce in response to strong sunlight, may lead to a greater risk of catching the coronavirus or suffering more severe effects of infection, according to some studies. Last week, researchers in Spain found that 82% of coronavirus patients out of 216 admitted to hospital had low vitamin D levels. The picture is mixed, however – some research shows that vitamin D levels have little or no effect on Covid-19, flu and other respiratory diseases.

Vitamin D deficiency can cause rickets in children and osteomalacia in adults – soft bones that lead to deformities – and children with severe vitamin D deficiency are prone to hypocalcaemia – low levels of calcium in the blood – which leads to seizures and heart failure.

However, Public Health England (PHE) and the Department of Health and Social Care have rejected calls over the past 10 years to fortify foods such as milk, bread and orange juice, which is the practice in Finland, Sweden, Australia and Canada.

“In my opinion, it is clear that vitamin D could not only protect against disease severity but could also protect against infection,” Davies said. “Food fortification would need careful planning to be rolled out effectively, particularly as people are now taking supplements. Picking the right foods to fortify would need to be done carefully.

 “But it’s clear that the current policy is not working – at least half the population have a vitamin D deficiency.”

Adrian Martineau, professor of respiratory infection at Queen Mary University in London, who is not part of Davies’s group, is leading a clinical trial to examine whether vitamin D can reduce the risk of Covid-19, or its severity. The Coronavit study, which began last week and is backed by the Barts Charity, the Fischer Family Trust and the AIM Foundation, will follow more than 5,000 people through the winter.

“The government recommends that the whole population takes vitamin D supplements in winter months, and those in high risk groups take it all year round,” Martineau said. “But we know that people just aren’t doing that in any significant numbers. Even I forget to take my supplement sometimes, and I’m living and breathing this subject. Fortification is a really good way of eliminating deficiency.”

Our bodies produce vitamin D in response to strong sunlight. In the UK, that means that from October to March, people need to rely on other sources: oily fish, eggs and food supplements.

Some foods, such as breakfast cereals and mushrooms are fortified with vitamin D, and people in low-income households are entitled to free multivitamins. White flour in the UK is already fortified with vitamins B1 (thiamin) and B3 (niacin), and last year the government began a consultation on adding vitamin B9 (folic acid) to help prevent spina bifida and other birth defects of the brain and spine.

A 2019 study at the University of Birmingham, led by Magda Aguiar, a health economist, showed there would be at least 25% fewer cases of vitamin D deficiency over the next 90 years if flour fortification were adopted, saving about £65m.

In 2017, Professor Louis Levy, PHE’s head of nutrition science, responded to calls for fortification by saying that there was not enough evidence that vitamin D would reduce the risk of respiratory infections.”


Of course, it is better to lockdown the economy and destroy livelihoods than to try out a simple vitamin fortification scheme, which would have health benefits anyway.



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Wednesday, 27 January 2021
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