Biotin (Vitamin B7)

    Written by:
    Daryl Nault

    Fact-checked

    by:

    Nick Milazzo
    Last Updated: September 12, 2023

    Biotin is one of the essential B vitamins used by the body primarily as an enzymatic cofactor. While it is popular as a beauty supplement for hair, skin, and nails and very preliminary evidence suggests it may have a role in these uses, its role is not well-supported. Potential interactions with diabetes are also not well understood.

    37 references on this page
    455 participants in 7 trials

    Overview

    Dosage information

    The only known supplemental dose of biotin that has been tested orally in humans — for the purposes of enhancing the quality of brittle nails — is 2.5mg taken once daily over six months.

    This dose appears relatively safe, although it is much higher than the recommended daily intake (RDI) of biotin which ranges from 25-30mcg (youth) upwards to 100mcg (adults). The biotin dose found in many multivitamins (30mcg or 0.03mg) seems more than sufficient.

    Frequently asked questions

    Update History

    Research Breakdown

    Examine Database References

    1. Blood glucose - Revilla-Monsalve C, Zendejas-Ruiz I, Islas-Andrade S, Báez-Saldaña A, Palomino-Garibay MA, Hernández-Quiróz PM, Fernandez-Mejia CBiotin supplementation reduces plasma triacylglycerol and VLDL in type 2 diabetic patients and in nondiabetic subjects with hypertriglyceridemiaBiomed Pharmacother.(2006 May)
    2. Multiple Sclerosis Symptoms - Bruce A C Cree, Gary Cutter, Jerry S Wolinsky, Mark S Freedman, Giancarlo Comi, Gavin Giovannoni, Hans-Peter Hartung, Douglas Arnold, Jens Kuhle, Valerie Block, Frederick E Munschauer, Frédéric Sedel, Fred D Lublin, SPI2 investigative teamsSafety and efficacy of MD1003 (high-dose biotin) in patients with progressive multiple sclerosis (SPI2): a randomised, double-blind, placebo-controlled, phase 3 trialLancet Neurol.(2020 Dec)
    3. Multiple Sclerosis Symptoms - Tourbah A, Lebrun-Frenay C, Edan G, Clanet M, Papeix C, Vukusic S, De Sèze J, Debouverie M, Gout O, Clavelou P, Defer G, Laplaud DA, Moreau T, Labauge P, Brochet B, Sedel F, Pelletier J, MD1003 (high-dose biotin) for the treatment of progressive multiple sclerosis: A randomised, double-blind, placebo-controlled study.Mult Scler.(2016-11)
    4. Multiple Sclerosis Symptoms - Sedel F, Papeix C, Bellanger A, Touitou V, Lebrun-Frenay C, Galanaud D, Gout O, Lyon-Caen O, Tourbah AHigh doses of biotin in chronic progressive multiple sclerosis: a pilot study.Mult Scler Relat Disord.(2015-Mar)
    5. Multiple Sclerosis Symptoms - Tourbah A, Gout O, Vighetto A, Deburghgraeve V, Pelletier J, Papeix C, Lebrun-Frenay C, Labauge P, Brassat D, Toosy A, Laplaud DA, Outteryck O, Moreau T, Debouverie M, Clavelou P, Heinzlef O, De Sèze J, Defer G, Sedel F, Arndt CMD1003 (High-Dose Pharmaceutical-Grade Biotin) for the Treatment of Chronic Visual Loss Related to Optic Neuritis in Multiple Sclerosis: A Randomized, Double-Blind, Placebo-Controlled Study.CNS Drugs.(2018-07)
    6. Triglycerides - Marshall MW, Kliman PG, Washington VA, Mackin JF, Weinland BTEffects of biotin on lipids and other constituents of plasma of healthy men and womenArtery.(1980)
    7. Nail Quality - Colombo VE, Gerber F, Bronhofer M, Floersheim GLTreatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopyJ Am Acad Dermatol.(1990 Dec)