Vitamin D is important for health. A deficiency can be prevented with food supplements. But beware: this too can be harmful.
Frankfurt – Especially in the dark season, when the weather is cold and uncomfortable, only a few people are taken out. The home office in times of the corona pandemic also means that fewer and fewer people are coming outdoors. This is particularly problematic for health. Because the human body needs sunlight, among other things, to produce an important vitamin: vitamin D.
It is extremely important for humans because it regulates the metabolism of phosphate and calcium and therefore contributes to the hardening of the bones. Vitamin D also promotes a functioning immune system and has an impact on muscle strength.
A vitamin D deficiency can therefore be harmful to health. As the Ärztezeitung summarizes, the list of diseases that could be related to the deficiency is getting longer and longer. It includes diseases such as susceptibility to infections, muscle weakness, heart attacks, diabetes, rheumatism, depression, Alzheimer’s disease, and multiple sclerosis. But when is there a shortage and what should be done about it?
Health: preventing vitamin D deficiency: this is how it works without pills and co.
According to the “German Society for Nutrition” (DGE), there is a deficiency if the serum concentration of the marker 25-hydroxyvitamin D is less than 30 nanomoles per liter of serum. This kind of shortage is not the case for the majority of the population in Germany. However, nearly 60 percent of Germans do not achieve the best possible blood concentration of 50 nanomoles per liter of serum, the specialist company points out.
As a result, more than half do not utilize the full health potential of vitamin D. But according to experts, pills and dietary supplements are not necessarily recommended for healthy people. Because the formation of the vitamin can be favored by an adapted lifestyle and a targeted diet.
Vitamin D: How Much Sunlight Is Needed?
Sunlight on the skin may be sufficient for the body to produce the required amount of vitamin D. However, how much important vitamin is actually produced depends on factors such as the season, the weather, clothing and skin type. Therefore, the suggestions of the DGE are to be understood only as guidance values. Between March and May in Germany ten to 25 minutes of tanning is sufficient, depending on the skin type. About a quarter of the body surface should be exposed to the sun, for example parts of the arms and legs, hands and face.
The skin type mentioned in the table refers to “light to very light skin color, light red or blond hair, and blue or green eyes” for skin types one and two. Skin type three is “medium complexion, dark hair and brown eyes”. The German Nutrition Society does not list any data for other skin types.
|Duration of exposure to sunlight for skin types I / II||Duration of exposure to sunlight in type III skin|
|From March to May: 10-20 minutes||March to May: 15-25 minutes|
|June to August: 5-10 minutes||June to August: 10-15 minutes|
|September to October: 10-20 minutes||September to October: 15-25 minutes|
|Source: German Society for Nutrition (DGE)|
Prevent Vitamin D Deficiency: These foods have a high concentration of the vitamin
However, these guidance values refer only to the period between March and October. But what’s the best way to behave in the dark season? Of course, it also helps to be in the sun in winter, but since the angle of incidence of the sun’s rays is very flat, there is not necessarily a significant production of the vitamin, as reported by the “Ärztezeitung”. The good thing about vitamin D is that it can be stored in the body. So, if you build up a supply of the vitamin in the summer, you can draw on it in the colder, less sunny months.
But the right diet can also help increase vitamin D levels. The concentration of this important vitamin is highest in oily fish such as herring and salmon. Eggs also have a significant concentration. Various mushrooms and liver are also recommended. However, the Federal Institute for Risk Assessment (BfR), for example, points out that the intake of vitamin D through food only plays a subordinate role. The focus is still on the formation of the body through sunlight.
|Food||Vitamin D (micrograms per 100 grams)|
|total of chicken eggs||2.90|
|Goudakäse, 45% F. i. tr.||1.30|
|Source: BfR nach Souci / Fachmann / Kraut, 2008|
Too much vitamin D: Overdose can be bad for your health
There are not only pills and supplements with vitamin D, some foods are now also fortified with vitamin D. However, the BfR points out that taking such supplements is only recommended if there is a proven vitamin D deficiency and the level cannot be improved by food or sun exposure. And this for one simple reason.
An excess of vitamin D can have a negative impact on health. The “Federal Institute for Risk Assessment” warns: “With a regular daily intake of over 100 micrograms of vitamin D, which with normal eating habits is currently only possible through excessive intake of vitamin preparations, undesirable effects such as kidney formation kidney stones or calcifications may occur. For medical reasons, however, higher vitamin D intake levels may be medically indicated. “
In addition to numerous studies, the Federal Institute for Risk Assessment has now recognized the connection between vitamin D deficiency and the risk of a severe course of Covid-19.
Vitamin D deficiency in risk groups: when experts recommend pills and the like
However, some groups of people belong to the vitamin D deficiency risk groups. This includes, for example, people who may only spend some time outdoors for health or other reasons (for example due to of a disease). According to the BfR, people who leave the house only with their bodies completely covered in clothing for cultural or religious reasons, or people with dark skin.
Older people also belong to the risk group, because the formation of vitamin D in the body decreases with age. In addition to the elderly, the risk group also includes the very young. Because babies only get a very small amount of the vitamin through breast milk and should be spared as much as possible from direct sunlight.
For these risk groups, taking a vitamin D supplement is recommended. However, only if a deficiency has been determined and your doctor recommends it to improve your vitamin level. (Sofia Lother)
The information provided in this article is not a substitute for a visit to a doctor. Only experts can make the right diagnosis and initiate adequate therapy. Taking medications or dietary supplements should be discussed with a doctor beforehand.