- Vitamin H
- Vitamin B7
- Coenzyme R
- W Factor
For Patients & Caregivers
How It Works
Biotin is widely available in foods. Biotin supplements are used to promote nail, skin, and hair health, but evidence is limited. Some people also use it for nerve, muscle, and diabetic symptoms. Patients should discuss use of this supplement beforehand with their doctor.
Biotin is an important coenzyme involved in sugar and fat metabolism. It is found in a variety of foods such as meat, vegetables, and eggs, and is also made in the intestines by bacteria.
Some studies show that taking biotin can benefit patients with multiple sclerosis or may improve diabetic nerve pain. Patients with diabetes may have a greater chance of being biotin-deficient. Consuming large amounts of egg whites or taking epilepsy drugs may also lead to biotin deficiency. However, there is no evidence for using biotin supplements in general, and deficiency in this nutrient is otherwise quite rare. In addition, too much biotin may weaken immune response and reduce the number of white blood cells. It may also cause inaccurate lab test results. Therefore, patients should consult with their doctor to determine the source of a true deficiency, or to discuss proper use of this supplement.
- To treat multiple sclerosis Preliminary data from a long-term study suggests that biotin is safe and may reduce symptoms in some patients. However, this study is ongoing and the final result is still not known.
- To treat diabetic peripheral neuropathy A small clinical study supports this claim. Larger studies are needed to confirm the effects.
- To treat brittle nails A small survey indicates that biotin may be effective. Further studies are needed.
- To treat hair loss Evidence is limited. According to one study, some women with hair loss may have lower biotin levels in their blood, but this does not mean it is the cause of it. In addition, there may be more than one cause. It is unclear if biotin is effective in preventing or treating hair loss in otherwise healthy people or in cancer patients due to chemotherapy.
- To treat infantile seborrheic dermatitis (a skin disorder) A small study showed that biotin was not effective in treating itchy, scaly skin.
- Taking high doses of biotin can incorrectly affect the results of many types of lab tests, including some used to detect heart or thyroid disease. It may also produce invalid results with some types of pregnancy tests. Therefore, it is important to tell your healthcare provider about any use of biotin supplements.
Do Not Take If
- You are undergoing lab tests such as blood or thyroid tests: There have been cases of biotin supplementation causing inaccurate test results. Therefore, it is important to tell your healthcare provider about any use of biotin supplements.
- You are taking a pregnancy test: Taking biotin supplements may cause an invalid test result.
For Healthcare Professionals
Biotin is an essential B vitamin that acts as an important coenzyme in carbohydrate and lipid metabolism. It is often taken alone or in combination with other vitamins for skin, nail, and hair health. It is also thought to help diabetes and neuromuscular disorders.
A small study suggests biotin supplementation may be effective in strengthening brittle nails (3). Low serum biotin levels have been associated with hair loss in some women but causes may be multifactorial (16), and evidence is limited (23) (24).
Other preliminary data suggest that high-doses of biotin may decrease symptoms of multiple sclerosis (17). Biotin may benefit patients with severe diabetic peripheral neuropathy (4). When taken with chromium, it may improve glycemic control in patients with type 2 diabetes (5). There are reports that biotin can reduce skin rash from gefitinib or erlotinib (18), but it did not reduce seborrheic dermatitis in infants (2). More studies are needed to confirm these observations. There is also not enough evidence to show that biotin is effective in preventing or treating chemotherapy-induced hair loss.
Biotin is abundant in foods including meat, vegetables, and eggs. True deficiency is rare but can be caused by a genetic disorder (13) or by malabsorption syndromes. Long-term use of certain anticonvulsant drugs can also induce biotin deficiency (11). These conditions can be treated by biotin supplementation.
Although biotin is generally safe, there are reports of interference with lab assays when taken in high doses (19) (20). In some hCG tests, biotin supplementation may also cause invalid test results (25). Surveys suggest that biotin supplement use is prevalent (26) (27), yet users may not report improvements in the condition they took it for, and lack awareness of potential lab test interference with use of this supplement (27).
Mechanism of Action
Biotin is an essential part of carbohydrate and lipid metabolism via carboxylase. It is converted into the free active form by the enzyme biotinidase, and can be synthesized in the intestine by bacteria (1).
Biotin induces microtubule formation in neurons (7), and biotin deficiency slows myelination (8) which may result in neuropathy. Biotin may reduce the activity of interleukins and interferons, and reduce the number of leukocytes (9).
Although biotin is generally safe, there have been cases of biotin supplementation interfering with certain lab tests, which may mask disease states, overestimate response to therapies, or subject patients to additional unnecessary diagnostic procedures (29).
Missed diagnosis of heart disease due to high intake levels of biotin: A patient death was related to falsely low troponin test results that were due to the patient’s high intake levels of biotin (22). Other papers also report the susceptibility of cardiac troponin assays to biotin interference at levels achievable with over-the-counter supplements (28).
Herb Lab Interactions
Immunoassay interference caused by high-dose biotin supplementation: Incorrect test results during routine follow-up of a 54-year-old female patient with progressive multiple sclerosis and Hashimoto’s thyroiditis (29).
Inaccurate troponin test results (22): A patient death was related to a missed diagnosis of heart disease, stemming from falsely low troponin test results that were due to the patient’s high intake levels of biotin. Other papers also report the susceptibility of cardiac troponin assays to biotin interference at levels achievable with over-the-counter supplements (28).
Free Thyroxine and Thyroid Stimulating Hormone (FT4/TSH) assay: Reported false-high values were attributed to high serum biotin levels in a neonate (12).
Qualitative urine hCG tests: Biotin supplementation may cause an invalid test result with some types of pregnancy tests due to absence of a control line (25).
Other immunoassay interferences: Biotin taken in moderate to high doses can result in either false-high or -low values (19).