Niacinamide, also called niacin or nicotinic acid, is a vitamin of the B complex. Like all vitamins, niacin performs vital functions in the body. In addition to building up and breaking down carbohydrates and proteins, the acid is involved in the formation of neurotransmitters. It also enables the regeneration of muscles, nerves and DNA.

The role of niacin in skin regeneration was clarified in the study of pellagra disease. This disease occurs in people with a very one-sided, but particularly low-protein diet. Besides diarrhoea and dementia, the symptoms include dermatitis, a "rough skin". Especially in light-exposed areas, the skin shows strong pigmentation, redness and increasing hornification. It was not until 1937 that the nutritional scientist and biochemist Conrad Elvehjem recognized the connection between the disease and an undersupply of niacin.

Applied dermally, niacin ensures regeneration of the skin barrier. In this process the acid participates in the build-up of lipids and ceramides which considerably contribute to the barrier function. Moreover, the vitamin prevents a too strong pigmentation by inhibiting the melanin synthesis.