Definition
Vitamin H is a water-soluble vitamin of the vitamin B complex, more precisely vitamin B7 or also called biotin. The intake of vitamin H to strengthen skin, hair and nails is particularly widespread; it is also found in this function in many preparations on drugstore shelves. But vitamin H fulfils many other functions.
As with other vitamins, in most cases no deficiency of vitamin H can be expected through a balanced diet. With a one-sided nutrition or also with rare genetically caused metabolic illnesses concerning the Biotinwechsel however a Hypovitaminose, i.e. a Vitamin H deficiency, can develop. A biotin deficiency can also occur as a result of a kidney dysfunction, which can lead to increased excretion of biotin in the urine. According to the German Society for Nutrition, a daily intake of 30-60 micrograms is sufficient for a healthy adult.
Occurrence and structure
Biotin is found in chocolate, nuts, egg yolk and liver, among other things, and is also produced by our intestinal bacteria. It is a urea derivative, which means that urea is part of its structure.
Function
Vitamin H fulfils a variety of functions in the human organism. For example, vitamin H plays a central role in the functioning of many metabolic pathways. Vitamin H is a so-called coenzyme, i.e. it plays a decisive role in the function of many enzymes.
Enzymes in turn have an important function in the metabolism of carbohydrates, fats and proteins. They accelerate many reactions in the body or make them possible in the first place, i.e. they act as catalysts. Vitamin H is also important for the lifespan of numerous cells, such as the cells of nervous tissue, the cells of the blood system, but also the sebaceous glands.
Biotin also has an important function in the cell nucleus and can change the readability of human DNA, i.e. it is also responsible for determining which genes can be read and which cannot. In the human body, there is a recycling process for biotin, i.e. biotin that has already been “used” for a metabolic reaction is returned to its original state by other enzymes and is thus available to the body for new metabolic reactions. However, this cycle is not completely closed, because biotin can be lost, for example, through excretion with the urine.
This must then be replaced by the biotin in the daily diet. Biotin is a cofactor in carboxylation reactions, i.e. in the attachment of carboxyl (C) groups. An example of reactions in which it participates is the first reaction of gluconeogenesis, i.e. the production of glucose (reaction of pyruvate carboxylase).
