This water-soluble vitamin is one of the ten members of the vitamin B complex group, and can be found in fish, dairy products, eggs, legumes, cabbage-family vegetables, and lean beef, among others.
Biotin is indispensible in metabolizing carbohydrates and fat, and is rarely found lacking in humans. In the unusual event someone does have a biotin deficiency, he will usually exhibit symptoms like dermatitis, loss of appetite, anemia, inflamed tongue, weakness, and muscle pain. The Food and Drug Administration has no Recommended Daily Allowance (RDA) value for biotin.