Like vitamins A and E, vitamin D is liposoluble. Vitamin D contributes to normal absorption and utilisation of calcium and phosphorus. This vitamin exists in two forms: vitamin D2 or ergocalciferol on the one hand, synthesised by yeast, and vitamin D3 or cholecalciferol on the other hand, synthesised in animals or humans by the action of ultraviolet B radiation. Exposure to UV radiation is essential to ensure adequate vitamin D intake. For this reason, vitamin D deficiency is extremely common in children and adults, especially in late winter and early spring in the northern hemisphere. In the West, up to 40% of the population over the age of 50 is vitamin D deficient.
The vitamin D Fisher uses is D3. It is more easily assimilated by the body than D2 and is therefore more effective. In addition, Fisher has selected a biological and vegetable form. Initially, natural cholecalciferol came either from the liver oil of fish such as cod or from lanolin, i.e. sheep’s wool fat and therefore of animal origin. There is now a 100% vegetable source of cholecalciferol thanks to lichen. This is the source of vitamin D3 that Fisher uses and is suitable for vegetarians and vegans because of its origins.