How does stress affect the lives of individuals? What is cortisol?

By: Sharanya

Edited: Ritisha Debnath

Mental, physical, and sociological habits are factors that affect people’s lives. Among these  factors is the stress hormone called cortisol. Cortisol is a steroid hormone—a glucocorticoid hormone created from the adrenal cortex, testes and ovaries. Steroid hormones are a specific type of hormone which enter cells and directly bind to nuclear receptors which alters the genetic expression and make changes to protein synthesis leading to long term effects in the human body. Cortisol is produced in the adrenal glands and it does more than just respond to stress and danger. It is an essential hormone in the body that regulates blood sugar levels, controls the use of proteins, fats, carbs, metabolism, decreases inflammation, and manages your circadian rhythm or sleep wake cycle. 

The biological system in which cortisol is released is called the hypothalamic-pituitary-adrenal (HPA) axis. The system gets activated whenever the brain detects a threat specifically stress, for example, physical stress, the hypothalamus sends a signal to the pituitary gland which instructs the adrenal cortex to release cortisol into the bloodstream. Cortisol increases blood sugar levels to keep the body alert and give quick energy, and also suppresses non-essential functions like digesting. The reason for this is that the central nervous system decides that energy needs to be conserved for immediate survival, therefore it slows down/stops the processing of food so that it can divert the internal energy to an immediate threat. This process is also known as the “fight-or-flight” response because in that time period, the nervous system instantly prioritizes survival before the prefrontal cortex has a chance to rationalize the situation. 

While this process is normal, complications arise when cortisol levels remain elevated for long periods of time. Elevated levels of cortisol lead to high blood pressure, weight gain especially in the face, headaches, weakened immunity, sometimes osteoporosis, as well as a risk of type 2 diabetes. In rare occasions, high cortisol leads to Cushing Syndrome which is a hormonal disorder whose symptoms are easily bruised skin, weight gain in the trunk with thin arms and legs, weight gain in the face (referred to as moon face), fatty lump between the shoulders (referred to as buffalo hump), acne, pink/purple stretch marks on body, bone loss, and stunted growth in children. On the other hand, low cortisol leads to symptoms such as fatigue, pain in the abdomen, unintentional weight loss, loss of appetite, and muscle weakness. A rare condition that occurs due to low cortisol levels is Addison’s disease (AKA primary adrenaline insufficiency) where there is complete damage to the adrenal glands. Common symptoms include: extreme tiredness, salt cravings, weight loss, dizziness, fainting, excessive sweating due to low blood sugar, muscle cramps, and upset stomach. Due to the reason that the human body needs this essential hormone, treatment is compulsory, often attained through lab grown hormones to supplement the replacing ones. 

Aging, in turn, can also minimally affect cortisol levels. Cortisol levels fluctuate in children and teens due to growth, puberty, emotional stresses. If in their childhood, a child has faced adversity or trauma, research shows that they might be prone  to addiction, obesity and other conditions. In adolescents, cortisol undergoes many changes during puberty such as a rise in basal or resting levels and elevated stress reactivity (heightened sensitivity of the hormone). As you grow older, cortisol levels might cause complications in menstrual cycles and pregnancy in women as they increase two to four times during that period. Unlike other hormones whose concentrations tend to decrease with age, cortisol continues to increase and cause irregularities in older adults. Genetics and environmental factors can potentially influence cortisol level as well. 

Ultimately, cortisol like every other hormone must be kept in balance. Complications can arise due to either low or high levels of the hormone, thus one must understand how to regulate cortisol in their body. Some tips that can help regulate cortisol levels are: moderate exercise, spend time outside (typically in the sun), performing somatic cortisol exercises and taking supplements if necessary.