Vitamin D3 – What is the well-known vitamin all about?

October 20, 2023
Vitamin D3 – Was hat es mit dem bekannten Vitamin auf sich?
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Vitamin D is also well-known for people who do not deal with vitamins and nutrients on a daily basis. This is mainly because vitamin D is one of the most commonly deficient vitamins and therefore often comes up in conversation. You should particularly focus on the topic in winter, as this is the time when there is the highest risk of a deficiency. However, not everyone knows the exact role of this important vitamin in the body. Vitamin D is used as a generic term for a group of fat-soluble vitamins and Vitamin D3 , more specifically cholecalciferol , is part of this group.  

But what is this well-known vitamin all about? How important is it in our body, how much do we need and where do we get it from?  



Body function

Vitamin D3 is required in many gene regulations and metabolic processes in the body, but its most important and primary role is in calcium and phosphate metabolism . Although the vitamin is also relevant for the immune system, the important role of this vitamin is to promote bone stability. By promoting the absorption of calcium and phosphates from the intestine and increasing calcium levels in the plasma, vitamin D ensures bone mineralization. Calcium is the mineral that is built into bones and keeps them both hard and stable. If you want strong, healthy bones, vitamin D is essential.  



In contrast to most other vitamins, the main source of vitamin D3 supply is not food. There are only a few foods that contain vitamin D (fatty fish, eggs and some edible mushrooms) and sufficient intake cannot be guaranteed. The special thing about vitamin D is that the main source is our body. However, sunlight is necessary for the body's own production of vitamin D , as it contains UV-B radiation, which is necessary for the production of the vitamin. The intensity and duration of radiation depend on the location of the country and the time of year. In Germany it is possible for the body to produce vitamin D outdoors from around March to around October. It is also possible for the body to build up vitamin D reserves for the winter, but many factors are important for this. It is therefore advisable, especially in the dark winter, to take care of your vitamin D stores by taking supplements.  

Since vitamin D is fat-soluble, you should also consume a little healthy fat when taking vitamin D supplements for optimal absorption of the vitamin.  


Daily requirements  

The German Society for Nutrition e. V. sets a daily requirement of 20 µg per day . Adolescents and adults only consume an amount of 2-4 µg per day through food. If sufficient sun exposure cannot be guaranteed, taking vitamin D supplements is recommended to cover the daily requirement.  



In countries where there is less sun, people are more likely to suffer from a deficiency, including countries in Central Europe, which includes Germany. In some Scandinavian countries, vitamin D is therefore also added to certain foods, such as dairy products.  

The risk group for a deficiency includes people who rarely spend time outdoors or when it is covered, and people with darker skin, as they allow less UV rays to pass through. Infants and older people are also at increased risk. In older people, the potential for their own production and metabolism of the vitamin decreases with age.  

A vitamin D3 deficiency can lead to significant risks and is not as rare as one might think. More than 40% of Germans have a vitamin D deficiency. For more information about the possible consequences of a vitamin D deficiency, you can read our magazine article: Vitamin D deficiency 



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