Researchers have found a link between cortisol levels in hair and behavioral problems in children.
- Study finds link between high cortisol levels in children’s hair and major behavioral problems.
- Children’s hair cortisol levels are also influenced by environmental noise. However, more research is needed to understand the association.
- For researchers, cortisol levels in hair could be a tool to assess chronic stress.
“Cortisol is usually present in blood, saliva, and urine, among other things, and indicates a momentary level of cortisol. However, cortisol accumulates in the hair. This indicates a long-term degree of stress, in other words, chronic stress.”explains Ane Arregi-Otxotorena from the Faculty of Psychology at the University of the Basque Country.
In this work, the researcher also discovered that children’s behavioral problems are linked to high levels of cortisol in the hair. In addition, exposure to factors likely to cause chronic stress can also be detected by hair cortisol levels.
The entire set of discoveries of the Spanish scientist and her team was presented in the journal Hormones and Behavior in August 2024.
High Cortisol Levels in Hair Linked to Child Behavioral Problems
For this research, Ane Arregi-Otxotorena took data from the INMA project, a multi-year study following families from pregnancy. She analyzed hair samples taken from 11-year-old children to evaluate the hormones present in the fiber.
The team’s first discovery: higher levels of cortisol in hair are associated with major behavioral problems seen in children such as difficulty managing their emotions, low self-esteem, hyperactivity and peer relationship problems… “It is important to note that maternal stress was positively related to behavioral difficulties in children”add the authors in their article. Thus, they suggest that maternal stress could also influence children’s hair cortisol levels.
In trying to understand the link between the level of this hormone in hair and behavioral problems in young people, they made another surprising discovery: cortisol levels are also influenced by environmental noise.
“Higher exposure to environmental noise is associated with lower cortisol levels. We saw that the higher the noise level, the lower the cortisol levels. When classifying the analysis by gender, this relationship was significant only in the case of boys.”the scientist specifies.
So, an initial acute stress caused by noise would lead to a temporary increase in cortisol levels, but chronic stress caused by long-term exposure to high noise levels would then reduce levels of the hormone. To try to understand this unexpected relationship, the researchers plan to conduct a new study on this precise point with a larger sample.
Hair cortisol levels could help understand the origin of chronic stress
For the researchers, this work highlights that simultaneous exposure to different environmental, social and individual characteristics impacts the concentration of hair cortisol. With the help of new studies allowing a clearer vision of this complex link, the level of the hormone in the hair could be a useful tool to assess the level of chronic stress, but also the presence of risk factors.
“This could help in the deployment of effective public policies. In fact, knowing what can cause chronic stress in the population in a specific place can facilitate the implementation of policies to prevent it.”assures the scientist in a press release.
