Biotin aids in cell growth; in fatty acid production; in the metabolism of carbohydrates, fats, and proteins; and in the utilization of other B-complex vitamins. Sufficient quantities are needed for healthy hair and skin. Biotin also promotes healthy sweat glands, nerve tissue; and bone marrow. In addition, it helps to relieve muscle pain. 

A deficiency in this vitamin can result in anemia, depression, hair loss, high blood sugar,  inflammation, or pallor of the skin and mucus membranes, loss of appetite, insomnia, muscle pain, nausea, and soreness of the tongue.