Biotin

Other Name(s):

vitamin H (archaic), coenzyme R, d-biotin, hexahydro-2-oxo-1H-thienol[3,4-d]-imidazole-4-pentatonoic acid

General Description:

Biotin is classified as a B vitamin. It is water soluble and readily absorbed when taken orally. It is found in a variety of foods and is also produced by bacteria inside the large intestine. Biotin deficiency is rare. Like the other B vitamins, biotin plays an important role in energy production.

Biotin works with carboxylase enzymes, ATP and magnesium to capture carbon dioxide for the synthesis of fatty acids. Biotin also plays an important role in the synthesis of proteins and purines. Biotin is important in carbohydrate metabolism and the metabolism of the amino-acid tryptophan.

Medically Valid Uses:

Biotin is the specific treatment for several genetic illnesses (biotinidase deficiency, propionic acidemia and holocarboxylase synthetase deficiency) caused by lack of certain enzymes. These illnesses can result in neurological damage and abnormal skin conditions, and occur with sufficient frequency that testing for them at birth may become a routine procedure similar to that of PKU.

Unsubstantiated Claims:

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

Biotin is claimed to be useful in treating alopecia (hair loss) and skin disorders such as acne, seborrhea and eczema.

Recommended Intake:

As indicated below, biotin is measured in micrograms (mcg). The DRI is the Dietary Reference Intake.

Biotin is stable at room temperature and therefore does not need to be refrigerated. It is not destroyed by cooking.

People who regularly consume a large number of raw egg whites (more than 6 per day) may become biotin-deficient. Egg whites contain a protein (avidin) that blocks the absorption of biotin.

Other people who need to take a biotin supplement are those who are immunodeficient or who have cirrhosis of the liver. People with the genetic condition phenylketonuria may require increased amounts of biotin.

Biotin requirements may be increased by the long-term use of some seizure medications (anticonvulsants), particularly carbamazepine and phenytoin.

Women who are pregnant or breast-feeding may need to take vitamin supplements, but should consult a physician before doing so.

No specific disease is associated with biotin deficiency. Biotin deficiency can lead to impaired glucose tolerance. Deficiency can also cause loss of appetite, nausea, muscle pain (myalgia), localized sensory changes (paresthesia), seborrheic dermatitis and nervous disorders such as depression.

Side Effects, Toxicity and Interactions:

There are no known problems associated with excessive use of biotin. Excess biotin is readily excreted in urine.

There are no known significant food or drug interactions.

Additional Information:

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References:

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11. Mock DM, Mock NI, Nelson RP, Lombard KA. Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. J Pediatr Gastroenterol Nutr. 1998;26(3):245-50.

12. Mock DM, Dyken ME. Biotin catabolism is accelerated in adults receiving long-term therapy with anticonvulsants. Neurology. 1997;49(5):1444-7.

13. Zempleni J, Mock DM. Bioavailability of biotin given orally to humans in pharmacologic doses [see comments]. Am J Clin Nutr. 1999;69(3):504-8.

14. Norrgard KJ, Pomponio RJ, Swango KL, et al. Double mutation (A171T and D444H) is a common cause of profound biotinidase deficiency in children ascertained by newborn screening the the United States. Mutations in brief no. 128. Online. Hum Mutat. 1998;11(5):410.

15. Thuy LP, Belmont J, Nyhan WL. Prenatal diagnosis and treatment of holocarboxylase synthetase deficiency. Prenat Diagn. 1999;19(2):108-12.

16. Norrgard KJ, Pomponio RJ, Hymes J, Wolf B. Mutations causing profound biotinidase deficiency in children ascertained by newborn screening in the United States occur at different frequencies than in symptomatic children. Pediatr Res. 1999;46(1):20-7.

17. Thuy LP, Jurecki E, Nemzer L, Nyhan WL. Prenatal diagnosis of holocarboxylase synthetase deficiency by assay of the enzyme in chorionic villus material followed by prenatal treatment. Clin Chim Acta. 1999;284(1):59-68.

18. Bender DA. Optimum nutrition: thiamin, biotin and pantothenate [In Process Citation]. Proc Nutr Soc. 1999;58(2):427-33.