Biotin is a member of the B vitamin family, which means your body does not produce it, so you must obtain it from your daily diet. Although it is only found in small amounts of certain foods, your body does not require large amounts. However, a biotin deficiency can cause various symptoms. While you should always consult with your physician before taking biotin or any other supplement, few side effects have been reported resulting from biotin supplementation — even with large dosages.
Biotin is a member of the B vitamins, which means it's water-soluble and any excess that you take is eliminated from your body.
Role of Biotin
The authors of a 2017 paper in Mini-reviews in Medicinal Chemistry stated that biotin helps the body break down amino acids, carbohydrates and fats. In addition to this main role, biotin also contributes to reproduction and development.
Researchers published an extensive list of foods containing biotin in the Journal of Food Composition and Analysis. This list shows that animal products and some vegetables have considerable biotin. Of the 87 foods tested, chicken liver and cow liver had the most biotin. Other sources of biotin include eggs, salmon, spinach, milk and bananas. While there's no specific data on biotin intake in the United States, according to the Office of Dietary Supplements, data from other western nations indicate most people get more than enough of this essential nutrient from the food they eat.
Upper Level Dosages
The recommended dosage for biotin for therapeutic effects can be anywhere from 30 to 100 micrograms per day for adults and teenagers, according to the Office of Dietary Supplements; however, no adverse side effects have been reported for taking biotin doses of up to 10 mg per day. For this reason, the Institute of Medicine did not identify a tolerable upper level for taking biotin. However, if you experience side effects you think may be related to taking biotin, report them to your physician.
Can't Take Too Much
Because biotin is a water-soluble vitamin, your body does not store the excess that builds up in your system. This means if you take more biotin than you need via supplementation, your body will likely release the extra biotin in your urine.
Who Needs Higher Doses
You may wish to take more biotin than the recommended dosages if you experience symptoms related to a biotin deficiency. Biotin deficiency symptoms include hair loss and developing a red rash around your eyes, nose, mouth and/or genitals. This rash is characteristic of a biotin deficiency, along with an usual distribution of fat in the face. You also may experience unexplained fatigue, hallucinations and numbness in your arms and legs.
Some people have a greater risk of biotin deficiency than others. The authors of a 2017 report in the Journal of Nutrition stated that biotin deficiency may spontaneously occur during an otherwise normal pregnancy. And, an animal study published in Gastrointestinal and Liver Physiology showed that the chronic intake of alcohol could trigger a biotin deficiency.
A genetic disorder called biotinidase deficiency may necessitate taking larger dosages of biotin than what is typically recommended. This condition affects the absorption of biotin in your intestines and keeps your body from using the biotin found in dietary protein sources like eggs, pork, salmon and liver. In this instance, high doses of biotin — anywhere from 40 to 100 mg of biotin per day — are recommended, according to the Linus Pauling Institute.
- MedlinePlus; Biotin; June 2011
- Linus Pauling Institute; Biotin; Jane Higdon, Ph.D.; June 2004
- National Academies Press; Biotin; Institute of Medicine; 1998
- Journal of Nutrition: Biotin
- Gastrointestinal and Liver Physiology: Inhibition of Intestinal Biotin Absorption by Chronic Alcohol Feeding
- Office of Dietary Supplements: Biotin
- Journal of Food Composition and Analysis: Determination of the Biotin Content of Select Foods Using Accurate and Sensitive HPLC/Avidin Binding
- Oncotarget: Anti-cancer Efficacy of Biotinylated Chitosan Nanoparticles in Liver Cancer