Rethinking biotin therapy for hair, nail, and skin disorders

The document discusses the role of biotin (vitamin B7 or H) in human metabolism and its importance in preventing neuromuscular dysfunction, alopecia, and dermatitis, as observed in biotin-deficient rats. Biotin deficiency in humans is rare but can result in similar symptoms. While biotin supplementation can be crucial for treating inherited metabolic disorders like holocarboxylase synthetase and biotinidase deficiencies, and high doses (300 mg/day) have shown benefits in reversing disabilities related to multiple sclerosis, there is no established daily allowance for biotin. The Institute of Medicine recommends 30 μg/day for adults, and typical Western diets provide an estimated 35-70 μg/day. The document highlights concerns about the widespread promotion and use of biotin for hair and nail improvement despite insufficient evidence to support its routine use and notes the FDA's warnings about the prevalence of biotin supplementation, which may not always be disclosed to physicians.