Hair Cortisol Concentrations Are Associated With Hair Growth Rate

The study investigated hair cortisol concentrations as a biomarker for metabolic diseases and chronic stress, involving 53 volunteers. Hair samples were analyzed using ELISA, revealing that daily hair washing resulted in lower cortisol levels compared to less frequent washing, while cosmetic treatments had no significant effect. Hair cortisol concentrations in the first 3 cm of hair correlated with an average growth rate of 1 cm/month, suggesting they reflect cumulative stress exposure over the past 3 months. These findings supported the potential use of hair cortisol as a biomarker for chronic stress assessment.