Stress and cortisol levels are normal biological response. In adults, several studies have explored how chronic stress and high levels of cortisol affect physical and mental health. Other studies have also explored the health effects of stress and cortisol levels in children.
Cortisol is a steroid hormone produced by the zona fasciculata of the adrenal cortex within the adrenal gland and released in response to stress and low blood glucose levels to activate anti-stress and anti-inflammatory pathways, as well as to assist in the conversion of fat, protein, and carbohydrates into energy.
The level of cortisol normally peaks early in the morning but start to drop in late morning and reach a low point at night. It appears stress and cortisol are normal part of everyday, healthy biological processes. However, several external factors might be stressing children resulting in high levels of cortisol. It is important to take note that cortisol levels are determinants of stress levels. Stress triggers the release of several hormones, including cortisol.
Despite having critical biological functions, several studies have linked stress and high levels of cortisol with a number of health issues and risks. In children to be specific, numerous studies suggest that high cortisol levels triggered by stressful circumstances can have profound negative effect on physical and mental health.
Disrupted metabolism is one probable health effect of stress and cortisol in children. According to researchers Panagiota Pervanidou and George P. Chrousos, chronic stress and high levels of cortisol contribute to the development of several metabolic syndrome, including abdominal obesity and other risk factors for diabetes and cardiovascular diseases. Researchers Y. Sen et al found out that blood cortisol were higher in children with metabolic syndrome than without. They concluded that there might be a link between cortisol production and metabolic syndrome in obese children and adolescence.
Another study by Paula L. Ruttle et al suggests that prolonged or sustained high cortisol levels often lead to biological adaptation as demonstrated by sustained low cortisol levels. This means that the levels of cortisol normalise over time due to prolonged exposure to stress. Sustained cortisol levels would eventually result in impaired or inefficient biological response to stress. Remember that the body releases cortisol in response to stress to activate important biological processes. Ruttle et al suggest that a disruption in biological responses is another health effect of chronic stress and high cortisol levels in children.
Stress and cortisol seem to affect the mental health of children as well. Irregular cortisol production pattern also correlates with behavioural problems in children. The same study by Ruttle et al revealed that some children with behavioural or mental problems such as aggression or depression have abnormally high levels of cortisol while others with identical problems have abnormally low levels. Although this might seem contradicting, the researchers concluded that cortisol levels were abnormally high around the time the behavioural problem emerged but eventually went abnormally low when the problem had been present for a long time. They theorised that the body eventually adapts to long-term stress caused by behavioural problems such as aggression or depression.
Even though it might appear that children with behavioural problems are actually coping as evident from their lowered cortisol level, they however developed a blunted response to stress. This would be detrimental because it might affect their biological and mental or behavioural response to certain distressful situations. Ruttle et al recommended that interventions should begin as soon as behavioural problems appear.
Another profound mental health impact of stress and high cortisol levels in children involves learning abilities. According to a study by Suor et al, children living in low-income households who endure family instability and emotionally distant caregivers are at risk of developing learning difficulties or impaired cognitive abilities due to higher levels of cortisol
Results of the study of Clancy Blair, Douglas Granger, and Rachel Peters Razza revealed that high cortisol levels in children due to exposure to impoverished household situations correlate with poor readiness for school. In testing cortisol levels and executive functions, the researchers specifically found out that children with higher cortisol levels have lower executive functions abilities than children with normal cortisol levels.
It is still unclear how cortisol levels affect cognitive abilities. However, researchers Suor et al mentioned that other studies have hypothesised that elevated cortisol levels can have toxic effects on parts of the brain that are important in cognitive functioning. Furthermore, low levels of cortisol might also be hindering the ability of the body to recruit the biological resources necessary for optimal cognitive functioning.
Pervanidou and Chrousos also highlighted the fact that children are vulnerable to the negative health effects of chronic stress and high cortisol levels simply because they are still in developmental stage. Developing brain structures and functions related to stress regulation, such as the amygdala, the hippocampus, and the mesocorticolimbic system, are more vulnerable to the effects of stress compared to mature structures in adults. In addition, chronic abnormalities in the pattern of cortisol production in children might affect the timing of puberty, final stature, and body composition.
Further details of the study of Pervanidou and Chrousos are in the article “Metabolic consequences of stress during childhood and adolescence” published in 2012 in the Metabolism Journal. More details of the study of Sen et al are in the article “Children and adolescents with obesity and the metabolic syndrome have high circulating cortisol levels” published in 2008 in the journal Neuro Endocrinology Letters.
Further details of the study of Ruttle et al are in the article “Disentangling psychobiological mechanisms underlying internalizing and externalizing behaviors in youth: Longitudinal and concurrent associations with cortisol” published in 2011 in the journal Hormones and Behaviors.
Further details of the study of Suor et al are in the article “Tracing differential pathways of risk: Associations among family adversity, cortisol, and cognitive functioning in childhood” published in 2015 in the journal Child Development. More details o the study of Blair, Granger, and Razza are in the article “Cortisol reactivity is positively related to executive function in preschool children attending head start” published in 2005 in the journal Child Development.