Cortisol is a hormone produced by the adrenal glands in response to stress (the adrenal glands are located on top of each kidney. There are two adrenal glands in the human body. These glands are part of the *endocrine system and play a crucial role in producing hormones, including cortisol).
It helps the body manage and adapt to stress by increasing the availability of substances that repair tissues and regulating metabolism by increasing blood sugar levels through gluconeogenesis (Khani and Tayek, 2001) the process of generating glucose from non-carbohydrate sources to ensure that the body has enough energy to handle stressful situations. Cortisol has potent anti-inflammatory properties. It can reduce inflammation by suppressing the immune system, but can be detrimental if it suppresses the immune response too much, for example, in the instance prolonged chronic stress.
Cortisol levels fluctuate throughout the day and night, typically peaking in the morning and gradually declining throughout the day, which helps regulate the sleep-wake cycle. If you produce too much cortisol throughout the day into the night, this is likely to affect how you sleep (Rodenbeck, et al., 2002; Brand, et al. 2012).
Chronic high levels of cortisol due to prolonged stress can have negative effects on cognitive function, including impaired memory (Buss, 2004; Kirschbaum, 1996). It can inhibit bone formation and decrease calcium absorption in the intestine, which can lead to weakened bone health if levels are high for prolonged periods. It also affects muscle tissue by breaking down proteins in muscle, which can be detrimental in excess.
Understanding cortisol is essential for improving wellbeing because chronic elevation of cortisol due to prolonged stress can lead to negative health effects, such as impaired immune function, disrupted sleep, and increased risk of various health conditions. Managing and regulating cortisol levels through stress reduction techniques and lifestyle adjustments is vital for promoting overall wellbeing.
*The endocrine system is a complex network of glands and organs that produce and release hormones, chemical messengers that regulate various physiological processes in the body. These hormones travel through the bloodstream to target cells or organs, where they influence growth and development, metabolism, mood, sexual function, and other essential functions. Key components of the endocrine system include glands such as the pituitary, thyroid, adrenal, and pancreas, among others. The system plays a crucial role in maintaining homeostasis and ensuring the proper functioning of the body’s internal environment.
References
Serge Brand; Edith Holsboer-Trachsler; José Raúl Naranjo; Stefan Schmidt, Interactions between evening and nocturnal cortisol secretion and sleep parameters in patients with severe chronic primary insomnia, Neuroscience Letters,Volume 324, Issue 2, 2002, Pages 159-163, ISSN 0304-3940, https://doi.org/10.1016/S0304-3940(02)00192-1.
Claudia Buss, Oliver Tobias Wolf, Joern Witt, Dirk Helmut Hellhammer, Autobiographic memory impairment following acute cortisol administration, Psychoneuroendocrinology,
Volume 29, Issue 8, 2004, Pages 1093-1096, ISSN 0306-4530, https://doi.org/10.1016/j.psyneuen.2003.09.006.
S, Khani., J, A. Tayek. Cortisol increases gluconeogenesis in humans: its role in the metabolic syndrome. Clin Sci (Lond) (2001) 101 (6): 739–747. https://doi.org/10.1042/cs1010739
C Kirschbaum, O.T Wolf, M May, W Wippich, D.H Hellhammer, Stress- and treatment-induced elevations of cortisol levels associated with impaired declarative memory in healthy adults, Life Sciences,
Volume 58, Issue 17, 1996, Pages 1475-1483, ISSN 0024-3205, https://doi.org/10.1016/0024-3205(96)00118-X.
Andrea Rodenbeck, Gerald Huether, Eckart Rüther, Göran Hajak, Influence of Mindfulness Practice on Cortisol and Sleep in Long-Term and Short-Term Meditators, Neuropsychobiology (2012) 65 (3): 109–118,
ISSN 0304-3940, https://doi.org/10.1016/S0304-3940(02)00192-1.