Roncuvita Biotin is an essential nutrient naturally present in some foods and also available as a dietary supplement. Biotin is the main vitamin that strengthens nails, hair and also improves skin health. A deficiency of biotin in the body will result in some health problems so people should maintain healthy levels of biotin in the body in order to avoid or overcome certain health issues. It is one of a type of B vitamins that is required by the body. Medical Experts also call it by the name B7 Vitamin or Vitamin H.