The Infatuation With Biotin Supplementation: Is There Truth Behind Its Rising Popularity? A Comparative Analysis of Clinical Efficacy versus Social Popularity

Biotin, also known as Vitamin B7 or vitamin H (the H comes from Haar und Haut, German for “hair and skin”), is a water-soluble B vitamin that acts as an essential cofactor for several carboxylases involved in the cellular metabolism of fatty acids, amino acids, and gluconeogenesis.^1,2,3 Biotin is also an essential cofactor for mitochondrial carboxylases in hair roots.^4,5 Although there exists a substantial amount of market advertising and social media publicity regarding the efficacy of biotin therapy for the improvement of hair quality, in reality the only human health condition for which there is strong evidence of biotin’s therapeutic utility is for the treatment of biotin deficiency.^1-6 Biotin deficiency may be acquired, in which case the most common causes are: 1) a lack of sufficient biotin in parenteral nutrition, 2) gastrointestinal abnormalities including malabsorptive disorders, 3) excessive intake of raw egg whites (raw egg whites contain avidin, a protein that binds biotin and renders it useless; cooking egg whites denatures avidin while biotin remains functional) and 4) chronic anticonvulsant therapy.^1,3,4 Biotin deficiency may also be inherited, in which case the most common causes are: 1) an inherited deficiency in holocarboxylase synthetase (an enzyme required to attach biotin onto biotin-dependent carboxylases; neonatal-onset of symptoms) and 2) an inherited deficiency in biotinidase (an enzyme required in releasing biotin from foods and biotin-related peptides; juvenile onset of symptoms).^1,4,5 In industrialized countries such as the United States, true biotin deficiencies remain rare because the production of biotin from intestinal bacteria remain sufficient to meet the body’s daily requirements.^2,3 For that reason, statutory agencies such as those in the United States do not prescribe a recommended daily intake of biotin.^2.2

In the mid-1980s, routine biotin supplementation for hair improvement was supported by both the pediatric and dermatologic communities. In fact, an article published in The Journal of the American Academy of Dermatology stated “It is a general recommendation that any child with unexplained hair loss, rash or candidiasis receive a trial of biotin therapy”.¹⁸However, to date, there have been no clinical trials conducted to evaluate the efficacy of biotin supplementation for any type of alopecia, and currently, its use to improve hair quantity or quality is not routinely recommended. ⁷ The initial literature investigating the efficacy of biotin for hair dates back to a study in 1965 in which 46 women were treated with an unknown dose of biotin and observed for “effects on hair roots”. The authors concluded that biotin supplementation produced no change in the “state of the hair roots” in any of the 46 women. ⁸ In the 1980s,