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Large population study: Lack of sun and vitamin D increases your risk of COVID-19 and new waves of the infection

Large population study: Lack of sun and vitamin D increases your risk of COVID-19 and new waves of the infectionA large Israeli population study of over 4.6 million people shows that lack of sunshine and vitamin D increases the risk of COVID-19 infections and new infection waves in the winter period. The study shows why seniors, those with chronic disease, overweight individuals, and certain ethnic groups such as orthodox male Jews and female Muslims are more vulnerable. The scientists recommend vitamin D supplementation throughout the winter period or even all year round for those who do not get enough sun exposure during the summer. You can also read about why face masks block the body’s vitamin D synthesis, why COVID-19 originates from bats, and other mysteries related to the spread of the infection.

Having sufficient amounts of vitamin D in your blood is of vital importance to the innate and the adaptive immune defense, which includes certain peptides in the respiratory tract that protect us against infections. The UV rays from the sun are our main source of vitamin D, which is synthesized when a cholesterol precursor in the skin is exposed to sunlight. Two things are required in order for the vitamin D synthesis to take place: Uncovered skin areas and sufficiently powerful sun. During the winter period where the sun sits low in the sky, vitamin D deficiency becomes more widespread, especially among people living at northern latitudes. It is the exact opposite in the southern hemisphere and this explains why COVID-19 waves are different, depending on whether you are south or north of Equator.
In Israel where the sun shines a lot more than in our part of the world, the general population has not had the same problems with COVID-19 infections. Still, two large ethnic groups are known for getting less sun exposure than others. One is the male ultra-orthodox Jews known for their full beards and large hats. The other is female Muslims that wear veils. For the sake of public health, a group of Israeli scientists from several different universities, health centers, and research centers wanted to look closer at how lack of sun and vitamin D affects COVID-19 infections.

Their study uncovered alarming vitamin D deficiencies

Israel has an electronic health register that has garnered comprehensive data on more than 4.6 million people for over twenty years. The data includes laboratory tests, diagnoses, and medical requirements. The scientists figured that they had a good chance of using these data to study the relation between blood levels of vitamin D and COVID-19 infections in 200 different places in Israel. They matched 52,405 corona-infected patients with a group of more than half a million healthy controls.
The scientists observed that lack of vitamin D (levels below 50 nmol/L) and especially severe vitamin D deficiency (less than 30 nmol/L) was far more common among ultra-orthodox male Jews. Female Muslims had an even greater risk with 81.5 percent having levels below 50 nmol/L. Among these, 59.1 percent had levels that were below 30 nmol/L. The scientists also found a direct link between the low vitamin D levels and widespread COVID-19 infections among these two ethnic groups. Other countries have also reported that there are alarming vitamin D deficiencies among various ethnic population groups.
On the other hand, the Israeli researchers found that COVID-19 infections were far less widespread among people with sufficient vitamin D levels. They write that COVID-19 infections are less likely to spread among people that have plenty of vitamin D in their blood because it strengthens the immune system and provides a type of flock immunity.
The scientists also looked at whether vitamin D supplementation over a period of four months had any influence on the risk of contracting COVID-19. They found that liquid vitamin D ingested as drops are most effective when it comes to protecting against COVID-19 infections, which is most likely because the liquid form of the nutrient is absorbed directly in the oral mucosa, which is the primary target of COVID-19. Vitamin D tablets are not absorbed before they reach the gastrointestinal tract. Furthermore, vitamin D is lipid-soluble which means tablets are not as good as taking vitamin D in oil in soft gelatin capsules.

The Israeli scientists claim that having enough vitamin D in the blood helps boost the immune system and creates flock immunity that makes it difficult for the virus to spread.

Full beard, obesity, bats, and other mysteries concerning vitamin D and COVID-19

As mentioned, ultra-orthodox male Jews have lower levels of vitamin D in their blood and a higher rate of COVID-19. They also had more infections than ultra-orthodox female Jews with the same low levels of vitamin D. The scientists theorize that this is because the virus can reside in the large beards and hats, from where it is easily transmitted to the mouth, the nose, or the eyes through hand contact. The researchers also mention that wearing a mask that covers part of your face lowers the body’s vitamin D synthesis. This is a real problem for those people that are veiled or fail to get enough sunlight for other reasons.
Another thing that the scientists observed that there were fewer COVID-19 infections among smokers. This observation supports a French study where scientists refer to the fact that many people smoke outdoors where there is less risk of contamination and where you get more sun exposure. There is also the possibility that nicotine has an anti-septic or anti-inflammatory effect. People are normally advised not to smoke because it is lethal for a number of reasons.
The Israeli researchers also found that overweight people with elevated blood pressure were generally more likely to have a COVID-19 infection, just like it is the case in other countries. Because vitamin D is lipid-soluble, it is stored in adipose tissue. This makes it difficult for the nutrient to reach the mouth and throat where the immune defense sets in with its primary attacks against the virus. It is also known that diabetics who are often overweight and hypertensive have difficulty with activating vitamin D in the liver and kidneys.
The Israeli scientists may even have an explanation to why coronavirus has mutated in bats and spread to humans. Bats sleep in their caves and other dark places during the daytime and their levels of vitamin D are often too low to measure. Therefore, bats have developed different ways to help minerals like calcium reach their bones. Their dark life and lack of vitamin D may have made the bats vulnerable to coronavirus, which can mutate and spread easily in large crowds.
We humans have also become more vulnerable to virus infections and other infections, simply because we spend too much time indoors and get too little vitamin D from sun exposure. Moreover, it is a fact that our ability to synthesize vitamin D decreases with age because our skin gets thinner as we grow older. With the growing number of seniors in today’s society, old people constitute a vulnerable group in terms of COVID-19 because they often lack vitamin D. People with dark skin also have difficulty with synthesizing enough vitamin D and therefore have a higher rate of vitamin D deficiency.

  • One billion people worldwide are believed to lack vitamin D
  • Vitamin D deficiency contributes to new waves of COVID-19

Time to act politically with inspiration from England

The Israeli scientists say that low blood levels of vitamin D are linked directly to the risk of COVID-19 infection and the risk of new waves that are controlled by the season. Their comprehensive report that was published in September 2020 states that the many observations should inspire politicians to recommend more sun exposure and the use of vitamin D supplementation before new, potentially lethal waves of the infection occur.
Unfortunately, these waves are already here because too little is done to address the problem. Still, the British government has decided to dole out free vitamin supplements to 2.2 million seniors, nursing home residents, chronically ill, and other vulnerable groups to help them in the battle against COVID-19. The aim of this is to stop the epidemic in its tracks and put an end to the constant lockdowns of society.
If other countries follow suit the effect will be much greater, simply because COVID-19 is a global problem and because vaccines only have a limited effect if COVID-19 mutates.

Effective vitamin D supplements

Normal vitamin pills contain very little vitamin D and many experts claim we need much more to optimize our blood levels of the nutrient. Vitamin D is lipid-soluble and it therefore best to take the nutrient in liquid form or as capsules with vitamin D dissolved in oil. High-dosed vitamin D supplements (20-80 micrograms) are available on the market. The individual need for vitamin D hinges on many factors such as sun exposure, age, skin type, BMI, and chronic diseases like e.g. diabetes.

  • When we synthesize vitamin D from sunlight, we make cholecalciferol – the form of the nutrient that is also found in supplements
  • Helped by enzymes, the liver converts cholecalciferol into the active form 25-hydroxyvitamin D3


Ariel Israel, Assi Circurel etb al. The link between vitamin D deficiency and COVID-19 in a large population. Department of Research and Data, Division of Planning and Strategy. 2020

Glenn Owen. Elderly and vulnerable will get free Vitamin D from government. Daily Mail. November 2020

José L Hernandez et al. Vitamin D Status in Hospitalized Patients with SARS-CoV2- Infection. The Journal of Clinical Endocrinology & Metabolism. 27 October 2020

Northwestern University. Vitamin D levels appear to play role in COVID-19 mortality rates. Science Daily. May 2020

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