RESUMO
Amino acids form a major component of hair fibres and are prescribed routinely in the form of nutritional supplements in patients with chronic telogen effluvium (CTE). Such a practice is based on assumption of a nutritional deficiency state in such patients. In this prospective study, we evaluated the serum levels of cysteine and arginine in 30 women with CTE and in healthy controls. We found no significant difference between the two groups in terms of serum arginine levels. Cysteine levels were higher in patients with CTE (P < 0.001). No correlation was found between levels of serum amino acids (cysteine and arginine) and either diet type (vegetarian or not) or body mass index, and no significant correlation between levels of the two amino acids and severity of disease. Our work suggests that arginine and cysteine deficiency is not present in women with CTE. Supplementation is unlikely to be of any benefit in nutrient-replete populations and only adds to the cost of therapy.