Vitamin D – The Sun Vitamin

Vitamin D – we can enjoy it as a direct gift from the Sun. When we expose the body to its rays, a unique substance is created in the skin which strengthens our immunity and bones. What do we really know about the solar vitamin?

Once upon a time… Life

Vitamin D has accompanied life on our planet since the beginning. 750 million years ago, phytoplankton could synthesize it in the ancient oceans. It was essential in the evolution from sea to land; Vitamin D helped to develop the skeletons of emerging species. Vertebrates have been able to produce vitamin D for about 300 million years.

When humans arrived as a new animal species, we were also able to synthesize Vitamin D. We thrive when there is enough Vitamin D in our body system. The lack of Vitamin D (Hypovitaminosis) can manifest visually noticeable deformities of the body’s frame, most often rickets. Currently its deficiency poses a higher risk for those with osteoporosis.

Facts about Vitamin D

Vitamin D is actually a steroid prohormone that dissolves in fats and occurs in plants and animals. In plants, ergocalciferol or Vitamin D2 is produced by the action of ultraviolet (UVB) radiation. In animals, UVB produces Vitamin D3 (cholecalciferol) due to UVB. So the best source is the sun and we naturally replenish the vitamin by staying outside. It is also not possible to overdose on Vitamin D produced naturally from the sun.

Nevertheless, experts estimate that 30-40% of UK people suffer from Vitamin D deficiency.

Why is this the case? Autumn, winter, early spring. These are the periods when we have a significant deficiency of Vitamin D. The reason is, of course, the lack of sunshine.

However, there are other causes of low Vitamin D levels. It may be due to insufficient exercise in the sun, excessive use of creams with a high protection factor, pregnancy, significant overweight or aging. With older age, less Vitamin D is synthesized in the epidermis (skin layer). Religious reasons, which in many states lead to the veiling of the body, may also play a role.

People with darker skin are particularly at risk of vitamin deficiency because their skin has higher protection against exposure as less UVB is released. This is the basis of the theory of lightening; the skin of the original inhabitants of the planet, who in the ancient past traveled from Africa to the Nordic countries. With this migration to places with reduced sunlight the need for Vitamin D gradually led to lower skin pigmentation.

The process of creating of Vitamin D

Let’s go into detail. Vitamin D is not produced directly in the skin. Its active form is the product of subsequent more complex operations in the liver and kidneys. Light on the skin is the trigger. Only after 10 to 15 minutes, when ultraviolet radiation (UVB) falls on the uppermost layer of the skin (epidermis), does the conversion of 7-dehydrocholesterol (Provitamin D) to Vitamin D3 begin. At his point it is its inactive state. Vitamin D is formed only by hydroxylation in the liver by the action of cytochrome P450. The active form of D3 is called 25-hydroxyvitamin D and serves doctors and scientists as an indicator of Vitamin D levels in the body.

Subsequently, hydroxylation produces 1,25-dihydroxyvitamin D3, which is the most active form of the vitamin. Only after the transformation in the organs does Vitamin D have the character of a hormone. The amount of Vitamin D in the body is determined by laboratory analysis and only then it is appropriate to use or adjust its dosage.

Benefits of Vitamin D to the body

All cells in the body contain receptors (VDR) for Vitamin D intake. This already proves how important it is for the body. Our grandmothers (and their grandmothers) already knew this when they said, Where the sun doesn’t go, the doctor goes.

Innate immunity

All vitamins are important for our immunity; however, the importance of Vitamin D has been a particular focus in recent years. It controls systems that protect cells from pathogens. In the event of an attack, Vitamin D activates white blood cells, more precisely NK cells (natural killers), which can deal with infectious agents (viruses, bacteria, parasites). Findings to date suggest that, for example, patients with acute or chronic infections should be provided with adequate Vitamin D intake. It’s a simple and inexpensive solution.

Infectious respiratory diseases

An infection is actually an attack on an organism from the outside. How Vitamin D protects our body from respiratory infections is illustrated by a survey conducted in the fall and winter of 2009-2010. Specialists from Greenwich Hospital in Connecticut, USA, investigated how 25-hydroxyvitamin D levels are associated with the occurrence of acute viral respiratory infections. They focused exclusively on months with low sunlight and compared the results in 195 healthy adults. Their conclusion is that a 25-hydroxyvitamin D concentration of 38 ng / ml or higher significantly reduces the incidence of acute respiratory diseases.

A number of studies are currently working on Vitamin D in relation to COVID-19. The results also point to the importance of optimal levels of sun vitamin in the body, as people with a deficiency are much more prone to the disease.

Bones and muscles

Our bones cannot do without calcium, and calcium cannot do without its Vitamin D regulator. And not just calcium. The sun vitamin ensures homeostasis and phosphorus production.

Vitamin D affects:

• release of calcium from bones and absorption into bones
• absorption of calcium into the blood
• calcium values ​​above 450 IU (International Units) affect bone health
• better muscle function and cell division

Vitamin D in food

Although we get the majority of our Vitamin D from the sun – about 90%, another source is vitamin-rich foods:

• most high-fat fish such as herring, eel or salmon
• egg yolks (did you know free-range eggs have up to 5 times more Vitamin D than those from caged hens)
• butter

Certain amounts of Vitamin D are also found in lard, bacon or beef liver. It should be noted that any heat treatment reduces the level of vitamins in our foof.

Ideal values

The ideal values ​​of Vitamin D are relative for each of us. It may be enough for a healthy adult to stay in the sun for 20 minutes at least twice a week. A senior should definitely double his stay in the sun. It is ideal to know your Vitamin D level and consult a doctor about appropriate supplementation. Not every body can assimilate the same amount from the same dose of Vitamin D.

It is recommended to take approximately 2000 IU daily to activate immune processes. But obese people need two to three times that value. In contrast, only 400 to 500 IU of Vitamin D is enough for children under one year of age. Other doses are suitable for infants, young children, pregnant women and postmenopausal women. In these cases, the recommended daily dose should be suggested by the treating physician.