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Vitamin D3 - the vitamin of the sun

Updated: Oct 24, 2023

Vitamin D3 has an amazing effect on our health. The best quality of this vitamin comes straight from the sun. It has a different chemical structure than the one we take in the form of a supplement. It turns out that its level in the body determines the susceptibility to infections, especially viral ones, as well as the course of the infection, and even mortality following a viral infection.

Vitamin D3 is often called the sun vitamin because it can be produced by the human body as a result of cholesterol transformations that occur under the influence of solar radiation. Vitamin D3, or cholecalciferol, is an organic chemical compound from the vitamin D group. In the characterization of vitamin D, two forms of this vitamin are the most important, vitamin D2 and vitamin D3. Vitamin D2 occurs naturally in plant organisms, while vitamin D3 occurs naturally in animal organisms. Vitamin D3 in the human body is traditionally considered a vitamin, but it's functioning as a prohormone.

Vitamin D3 - the vitamin of the sun
Vitamin D3

This vitamin, when converted into its active form, behaves like a hormone. It binds to the intracellular receptor and activates genes. We know the many functions of this vitamin. It has also been shown that its deficiency is associated with such autoimmune diseases as multiple sclerosis, rheumatoid arthritis, systemic lupus, type I diabetes, and inflammatory bowel diseases. Vitamin D3 reduces the activity of the autoantigens of dendritic cells - the guardians of the controllers. It is from their alarm that the entire cascade of inflammatory reactions begins.

Moreover, vitamin D3 affects the functioning of several important systems in the human body:

Immune system

- vitamin D3 has an immunomodulating effect but also an indirect antibacterial effect. Additionally, vitamin D3 has anti-proliferative and anti-cancer properties. Some studies have shown that it can reduce the possibility of getting the flu.

Muscular system

- vitamin D3 deficiency can cause myalgia, which is muscle pain,

Skeletal system

- a sufficient supply of vitamin D3 in the body is extremely important for the skeletal system because this vitamin affects bone metabolism. In adults, vitamin D3 deficiency can lead to osteoporosis.

Nervous system

- vitamin D3 is very important for the proper functioning of the nervous system. The deficiency of this vitamin can cause sleep disturbance in the patient.

Circulatory system

- A study, published in the "European Heart Journal", shows that vitamin D deficiency can cause heart disease and higher blood pressure

Multi-tissue metabolism

- vitamin D3 affects the ability to regenerate the liver. It can also work against cancer.

Support for skeletal system, immune system, nervous system, circulatory system, multi-tissue system
Vitamin D3

Most people have blood levels of vitamin D3 between 20 and 30 ng/ml. While optimal, according to new medical recommendations, is 70-90 ng/ml. Serum concentrations of 150 ng/ml and more are considered harmful. Therefore, the level of the 25 (OH) D metabolite should be tested and, above all, your well-being should be monitored.

The safe upper limit of intake is set at 4,000 IU per day. Intake in the range of 40,000–100,000 IU per day (10–25 times the recommended upper limit) has been linked with toxicity in humans. The main consequence of vitamin D3 toxicity is hypercalcemia, with symptoms including nausea, vomiting, weakness, and kidney failure. Treatment involves limiting all vitamin D3 intake and sun exposure. Vitamin D3 toxicity usually develops over time, and the harmful effects are very complex. Large doses may cause damage, despite a lack of noticeable symptoms. However, every human is different and our organisms are not the same, that's why it is crucial to check the 25 (OH) D level.

Hypercalcemia is a condition in which the calcium level in the blood is above normal. Too much calcium in the blood can weaken bones, create kidney stones, and interfere with how the heart and brain work. Hypercalcemia makes it hard for the body to carry out its normal functions. Vitamin D3 deficiency is very common in our climate zone, so it is worth consuming much more in periods of lack of sun. The skin pigment has a lot to do with how well our skin absorbs UVB. The more melanin in the skin (the darker the skin), the fewer UVB rays can penetrate. The weight can also affect the D3 production system. Remember, vitamin D is a fat-soluble vitamin. The more fat cells the body has, the more we may be at risk of a D deficiency because the vitamin D3 in the body becomes trapped in those fat cells.

Age is also crucial in vitamin D3 intake. As we get older, it naturally becomes more difficult to convert sunlight into D3. For example, when exposed to the same amount of UVB radiation, a person who is 70 years old will make 75 % less D3 than a 20-year-old.

Source of Vitamin D3
Source of Vitamin D3

To sum up "vitamin D3 has a critical role in the innate immune system through the production of antimicrobial peptides - particularly cathelicidin. Vitamin D3 appears to have an important role in the respiratory tract, skin, and potentially gut health. Several autoimmune diseases, including multiple sclerosis, Type I diabetes, systemic lupus erythematosus and rheumatoid arthritis, are associated with vitamin D3 deficiency. Vitamin D3 could have an important role in the prevention and possible treatment of these conditions; however, much of the current evidence relates to basic science and epidemiological research." - Pub Med

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