Children’s Hair Cortisol and Hair Testosterone Concentrations in Response to Environmental Changes: From Summer Holidays to School

A study conducted on 60 school children aged 10-12 years over a four-month period found that the transition from summer holidays to school affects hormone production differently in girls and boys. In girls, hair cortisol concentrations increased during school compared to summer holidays, partly due to peer and emotional problems. In boys, hair cortisol and testosterone concentrations were significantly higher, with cortisol increasing slightly and testosterone decreasing significantly during school. The study suggests that school and its related demands represent a stressor, affecting both hormonal axes, though in a reverse manner for girls and boys. The study was the first to perform a combined analysis of stress-related changes in hair cortisol and testosterone in children over a period of four months. However, it had limitations including the hair sampling approach and potential seasonal effects in hormone concentrations.