Comment on the Use of Biotin for Hair Loss

quirements, and biotin is consumed from a wide range of food sources. The first demonstration of acquired biotin deficiency in animals was observed in rats fed raw egg white [4], due to a glycoprotein found in egg white, avidin, which binds extremely well with biotin, making it unavailable for use in enzymatic reactions. Ultimately, Patel et al. [1] conducted a PubMed search of case reports and randomized clinical trials with biotin supplementation with the aim of systematically reviewing the literature on biotin efficacy for disorders of hair and nail growth. They found 18 reports on improvement in hair and nail growth following supplementation in patients with established biotin deficiency; however, they propose that these cases are uncommon, and therefore there is a lack of evidence for biotin supplementation in healthy individuals. They claim that there are currently no studies that show biotin deficiencies in healthy human individuals with balanced diets, and despite recognition of one recent study demonstrating a frequency of 38% biotin deficiency (<100 ng/L) in a collective of 541 women complaining of hair loss [5], they dismiss this finding as confounded by multiple factors, including a patient history of use of antibiotics, antiepileptics, isotretinoin, or gastrointestinal disease in 11%, and coexisting seborrheic dermatitis in 35% suggesting a multifactorial cause for the hair loss. While the frequency of biotin deficiency in the general population has not yet been established, it is remarkable that biotin levels were found to be deficient (<100 ng/L) in 38% and marginal (between 100 and 400 ng/L) in 49% of women complaining of hair loss [5], whatever the causes may be. It is regretful that Patel et al. [1] did not acknowledge and reiterate the recommendations regarding biotin for women with hair loss from the respective publication [5]: “In view of the frequency of biotin deficiency in women complaining of hair loss, a careful patient history and clinical examination with respect to risk factors for biotin deficiency (gastrointestinal disease, medication with isotretinoin, antibiotics, or antiepileptics) and associated symptoms of biotin deficiency (seborrheic-like dermatitis, neurological symptoms) must be performed. When biotin deficiency is suspected, the serum biotin level must be determined, and in case of biotin deficiency (<100 ng/L), the cause must be sought (unless obvious from the patient history) and treated. Regardless of the cause, biotin deficiency is successfully treated with nutritional supplementation with a usually high bioavailability of oral biotin in a dosage of 5 mg/day. At the same time, potential additional causes of hair loss, such as androgenetic alopecia, other nutritional deficiencies, and endocrine disorders, must be systematically addressed and treated as well.” I totally agree with Patel et al. [1] that the custom of treating hair loss in an indiscriminate manner with oral biotin supplementation is to be rejected, and that there is a need for randomized controlled studies to validate the additional benefit of biotin supplementation in individuals with hair loss of multifactorial origin with biotin deficiency or marginal biotin levels. Knowledge is in the end based on acknowledgement. Ludwig Wittgenstein (1889–1951)