Close Big menu

Learn everything from the production to the effect of the products.
If you have any questions, please contact us.


Strath products are also available in pharmacies, drugstores and health food stores.

Our products

Take a look behind the scenes at Bio-Strath and get to know us. For everything else, contact us.

Woman throws autumn leaves into the air with joy

Vitamin D

The sun vitamin

Vitamin D supports the immune system and makes us less susceptible to pathogens. It positively influences the maintenance of bones and teeth and supports the growth of children. Vitamin D also controls many important functions, including contributing to normal muscle function.

The importance of the skin in vitamin D formation

The special thing about vitamin D is that it can be synthesised by the body itself. Vitamin D is produced by the UVB rays of sunlight on the skin. However, the formation of vitamin D in our skin is influenced by various factors:

  • From November to May, the sunlight in Europe is not enough to produce enough vitamin D.
  • Furthermore, with increasing age, the ability to produce vitamin D is reduced by a factor of 4.
  • In addition, older people often avoid direct sun exposure.
    Other, age-independent risk factors for vitamin D deficiency include:
  • Obesity
  • Poor absorption of nutrients in the intestine
  • Consistent application of sunscreen.
    And don't forget that there is an increased need for vitamin D during pregnancy and breastfeeding as well as in children.

Sources of vitamin D intake

Vitamin D only from food?

That is not enough. Of course, we also take in vitamin D through our diet. However, the sources of vitamin D intake are limited. Vitamin D is fat-soluble and therefore occurs mainly in fatty foods.

  • Larger amounts are mainly found in fatty fish such as salmon, sardines or mackerel.
  • However, to achieve a sufficient intake of vitamin D from food, 2 portions of fatty fish would have to be consumed daily.
  • Non-animal sources of vitamin D are very sparse and cannot cover the daily intake by far.
  • Vegan vitamin D is found, for example, in chlorella (freshwater algae), avocado and mushrooms.
Recommended dose

Since vitamin D deficiency is widespread and sunlight and diet are not reliable sources of sufficient vitamin D supply in Switzerland, the Federal Office of Public Health has issued the following recommendation for vitamin D supplementation of the diet with supplements:

  • From the age of 60, 800IE (IU = international unit) per day.
  • From the 2nd to the 59th year of life, 600 IU per day
  • From the 1st year of life, 400 IU vitamin D per day

Food supplementation with vitamin D supplements in these amounts is well tolerated and ensures that vitamin D deficiency can be corrected in over 97% of the population. Vitamin D blood level measurement before starting supplementation is not generally recommended.

The Strath Food supplement with natural vitamin D is based on high-quality vitamin D herbal yeast. The vital substance-rich food supplement is suitable for children, adults, pregnant women, nursing mothers, students, professionals, athletes and older people. The recommended daily amount of 15 ml can be taken long-term and there is no risk of overdose.

A daily adult dose of 15ml of Strath supplement contains 6 μg or 240 IU of vitamin D, which covers 40% of the Federal Office of Public Health's requirements for the daily recommended need. The improved absorption of vitamin D through Strath herbal yeast, a balanced diet and sensible sun exposure fully cover the daily requirement of vitamin D and prevent vitamin D deficiency in the long term.

Bio-Strath knowledge

Read more