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Vitamin D

Vitamin D

Vitamin D3, or cholecalciferol, is not a vitamin in the proper sense. It is a hormone derived from the stress hormone, cortisol.


Vitamin D is the result of the molecular transformation of cortisol under the skin, under the influence of sunlight, particularly UVB (ultraviolet light with a wavelength of 300 nm).


The main function of vitamin D3 is to maintain and regulate the metabolism of calcium in the body. Consequently, it is crucial for the development and preservation of a strong and healthy skeleton. Vitamin D insufficiency increases the risk of osteoporosis, but it is also associated with an increased risk of high blood pressure. 1, 2, 3 As a result, there is an increasing awareness of the importance of sufficient levels of vitamin D3 as a condition for optimal health. Vitamin D is transformed into its biologically active form in the skin through the photochemical conversion of provitamin D and additional transformation in the liver and the kidneys. However, the UVB rays required to achieve the transformation are not present all year round in regions with a latitude of under 35 °.4 For those living north of this latitude, it is essential to ensure a daily intake of vitamin D. Very few dietary sources naturally contain vitamin D. This often leads to low plasma levels. The general population does not respect the minimum requirements for vitamin D. 5, 6, 7 This is particularly true for people who spend most of their time indoors, or who have dark skin. Oily fish contains the highest levels of the vitamin. Vitamin D2 is produced by mushrooms. It has also been discovered that vitamin D has a significant modulating effect on the adaptive and innate immune system, and on deficiencies associated with upper respiratory tract infections such as colds, bronchitis and the flu 9,10. Vitamin D3 plays such an important role in resistance because it transforms the immune cells to produce substances that have a powerful effect against a range of bacteria and viruses. 11,12 Recent research demonstrates that vitamin D3, in addition to the winter diet, is the safest way of reducing the number of cases of flu and infections in children, and in particular in children with a vitamin D3 deficiency.13, 14, 15

Bibliographical references

The health claims that feature on our website in relation to the plants contained in our products are compliant with the list of health claims awaiting final assessment by the Community authorities (cf. website of the European Commission: http://ec.europa.eu/nuhclaims/). However, they may be subject to modification following their assessment by the national competent authorities.

The health claims relating to other nutrients or substances contained in our products that feature on our site are compliant with Regulation No. 432/2012 of the Commission of 16 May 2012 which establishes a list of authorised health claims authorised in relation to food products, other than those in reference to the reduction of the risk of disease as well as community-based development and child health (cf. website of the European Commission: http://ec.europa.eu/nuhclaims/).