Vitamin D3

Vitamin D is very important for human health. Vitamin D contributes to the normal function of the immune system.

Most of the vitamin D that people need for their health is produced through the skin. This requires sunlight, which - if too strong - can cause massive damage to the skin. The production in the skin depends on various factors: skin type, age, duration of sun exposure and also the use of sunscreen.

In general, it can be said that our skin can produce enough vitamin D in the summer months in Central Europe and supplementation during this time is only useful for certain groups (e.g. pregnant and breastfeeding women, people over 60 years of age). In late autumn, winter and early spring, however, the sun is too weak for the skin to produce enough vitamin D. The latest studies show that during this time, vitamin D levels in the Swiss population can fall below the recommended level.

The official health claims for vitamin D are as follows:
- Vitamin D is needed for healthy growth and development of bones in children.
- Vitamin D contributes to the normal absorption and utilization of calcium and phosphorus.
- Vitamin D contributes to normal calcium levels in the blood.
- Vitamin D contributes to the maintenance of normal bones.
- Vitamin D contributes to the maintenance of normal muscle function.
- Vitamin D contributes to the maintenance of normal teeth.
- Vitamin D contributes to the normal functioning of the immune system.
- Vitamin D has a function in cell division.
- Vitamin D helps reduce the risk of falls caused by postural instability and muscle weakness. Falls are a risk factor for bone fractures in men and women over 60 years of age.
- Vitamin D contributes to the normal function of the immune system in children.

Normally, only 10 - 20% of the daily requirement of vitamin D3 is covered by our diet. The majority is produced in the skin through exposure to sunlight.

Vitamin D is mostly obtained from animal sources, especially fish. The largest sources of vitamin D are cod liver oil and fatty fish such as salmon, herring and mackerel. Significantly less vitamin D is found in chicken eggs, margarine, liver and various types of meat.

Plant-based vitamin D (vitamin D2) is found in mushrooms and avocados, for example.