In terms of human nutrition vitamins D2 and D3 play the most important role. In human body these vitamins can be produced by the sunlight influence (D3) or supplied together with a meal (vitamins D2 a D3).
Lack of vitamin D is a global problem.
Epidemiologic studies have proven that deficit of this vitamin is present in the all age groups.
The most common reason of the lack of vitamin D is a lack of exposing to the sunlight due to lifestyle (work in the interiors) as so as some fear of exposure to the sun and using the cosmetics with UV filters.