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 phenylketonuria (PKU).

Unsubstantiated claims

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

Biotin has been said 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.



Adults (11+ years)

30 mcg

Pregnant women

30 mcg

Breastfeeding women

35 mcg


Food source

Nutrient content per 100 grams

Brewer's yeast

188.8 mcg


179.4 mcg

Beef liver

113.3 mcg


94.3 mcg

Split peas

77.7 mcg

Sunflower seeds

66 mcg

Green peas/lentils

40 mcg


37.5 mcg


27.75 mcg


18.9 mcg

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 PKU 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 breastfeeding may need to take vitamin supplements, but should consult a physician before doing so.

Certain rare, genetic disorders are 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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