Biotin (vitamin H or vitamin B7) is a B-complex vitamin that acts as an essential coenzyme for five carboxylases: pyruvate carboxylase, 3-methylcrotonyl-CoA carboxylase, propionyl-CoA carboxylase, and coenzyme for acetyl-CoA carboxylases 1 and 2. These carboxylases help in several chemical processes in the cell, including gluconeogenesis, amino acid metabolism, and fatty acid synthesis. The Food and Nutrition Board of the Institute of Medicine recommends a daily dietary intake of 30 mcg/day, for the maintenance of good health. Biotin deficiency is very rare in those who take in a normal balanced diet. Mammals obtain biotin from food. Foods rich in biotin are egg yolk, liver, cereals (wheat, oats), vegetables (spinach, mushrooms), and rice. Dairy items and breast milk also contain biotin.