Sun Vitamin: Detecting and Treating Vitamin D Deficiency

Vitamin D is an essential vitamin that influences numerous bodily func...

Vitamin D is an essential vitamin that influences numerous bodily functions. It is involved in the absorption of calcium and phosphorus for strong bones, as well as in the normal function of the immune system and the nervous system. Consequently, vitamin D deficiency can have far-reaching effects. It is therefore important to recognize a vitamin D deficiency early and treat it properly.

What is vitamin D?

Vitamin D belongs to the fat-soluble vitamins and is often referred to as the sunshine vitamin. It is involved in maintaining healthy bones and teeth through calcium and phosphate metabolism, among other things. It also affects other aspects such as the nervous system and the immune system. As an essential vitamin, we depend on external intake.

There are basically two main forms of vitamin D: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). The first form is produced when UV rays from the sun hit plant organisms like mushrooms. Cholecalciferol is produced when UV-B rays hit the skin.

In the body, vitamin D2 or D3 is metabolized into calcitriol in the liver and kidneys. This active form of vitamin D is involved in metabolic processes, such as regulating calcium and phosphate metabolism.

Natural sources of vitamin D

Humans are capable of producing vitamin D themselves when UV-B radiation hits the skin. Therefore, people with vitamin D deficiency are recommended to sunbathe daily. Midday is the best time for the skin to synthesize vitamin D. By the way, vitamin D is not produced through windows because the glass filters out the necessary UV-B radiation.

Otherwise, people can also obtain vitamin D from their diet. The following sources are particularly noteworthy:

Fish: Fatty fish like salmon, herring, or mackerel contain a lot of vitamin D and can therefore be eaten more frequently in case of a deficiency.
Fish liver oil: Fish liver oil contains especially high amounts of vitamin D, with preparations from cod being particularly recommended. Please ensure sustainable fishing when purchasing such preparations.
Egg yolk: Egg yolk also contains quite a lot of vitamin D, although the exact content can vary depending on the chicken breed, feeding, and husbandry.
Mushrooms: Certain types of mushrooms contain relatively high amounts of vitamin D, especially if treated with UV-B radiation. Dried shiitake mushrooms are an example.
Fortified foods: Especially Nordic countries fortify certain foods like dairy products, margarine, or cereals with vitamin D. This is intended to prevent deficiency in the population.

What are possible causes of vitamin D deficiency?

Many factors can cause vitamin D deficiency. If suspected, you should see a doctor. In principle, the following causes could lead to or promote vitamin D deficiency:

Lack of sun exposure: Those who spend little time in sunlight produce little vitamin D themselves.
Geographic location and season: The farther you live from the equator, the lower the intensity of sunlight. In Iceland, for example, vitamin D supplementation is part of everyday life.
Darker skin color: The more melanin in the skin, the more UV-B rays are absorbed. Consequently, less vitamin D can be produced.
Age: Older skin can produce vitamin D less effectively.
Nutrition: Too few foods containing vitamin D can also promote a deficiency.
Fat absorption: If fat absorption in the intestine is impaired, less of the fat-soluble vitamin D may be absorbed.

Symptoms of Vitamin D Deficiency

The symptoms are often diffuse and not explicitly attributable to a vitamin D deficiency. Therefore, a doctor’s visit is important. The following symptoms may occur:

fatigue and exhaustion
muscle weakness
bone pain
Osteoporosis with long-term deficiency
Frequent infections
mood swings
hair loss
Delayed wound healing

If you notice one or more of these symptoms, you should see a doctor. They can make the appropriate diagnosis.

Diagnosis of Vitamin D Deficiency

To address vitamin D deficiency with your doctor, a diagnosis must be made. The diagnosis is quick and simple through a blood test. This measures the 25-hydroxyvitamin D level, also known as the 25(OH)D level. This measures a breakdown product of vitamin D. Results are given in nanograms per milliliter (ng/ml). Values between 20 and 50 can be considered insufficient. Officially, a vitamin D level above 30 is considered sufficient.

Prevention and Treatment of Vitamin D Deficiency

To prevent vitamin D deficiency, three points are recommended: increased sunlight exposure, vitamin D-rich diet, and vitamin D supplements. However, supplements should only be taken if a deficiency is very likely, as too much vitamin D can be harmful to health. Increased sun exposure is considered the best preventive measure.

Vitamin D treatment is usually done with dietary supplements. Your doctor will discuss the correct dosage and frequency of intake with you, as this also depends on the severity of the deficiency. In the long term, lifestyle changes and dietary optimizations can help, although dietary supplements remain the treatment method of choice. The goal is ultimately to replenish the vitamin D stores.

Vitamin D deficiency: Frequently asked questions

What happens with vitamin D deficiency?

Vitamin D is involved in numerous metabolic processes in the body. These metabolic processes do not function properly in the case of a deficiency, which can manifest in symptoms such as exhaustion, muscle weakness, or osteoporosis. If you notice symptoms of such a deficiency, please consult a doctor promptly.

How does a vitamin D deficiency manifest?

A vitamin D deficiency can manifest through the following symptoms:

fatigue and exhaustion
muscle weakness
bone pain
osteoporosis
increased infections
mood swings
hair loss
delayed wound healing

What is a normal vitamin D level?

In blood tests, the 25-hydroxyvitamin D level is usually measured. This measures breakdown products of vitamin D to allow conclusions about the level of active vitamin D. Officially, a deficiency is present if the value is less than 30 ng/ml. Values below 50 ng/ml can be considered insufficient.

What does vitamin D do?

Vitamin D can especially be found in the following foods:

Fish
Fish liver oil
Egg yolk
Mushrooms
Fortified foods

Alternatively, warm sunlight exposure is highly recommended to increase vitamin D levels in the bloodstream.

How important is vitamin D?

Vitamin D is very important; a deficiency can have far-reaching consequences. In particular, osteoporosis and osteomalacia should be mentioned here. Additionally, a lack of vitamin D can significantly reduce quality of life, for example by causing increased fatigue, hair loss, and bone pain as well as muscle weakness. Delayed wound healing can also cause major problems.