Cortisol is a hormone that is secreted from the adrenal glands and is of great importance to the stress response. When one encounters a stressor, cortisol is released at greater magnitudes than normal. While small increases of cortisol have positive effects such as having increased energy, heightened memory function, increased ability of immune system, decreased sensitivity to pain, and maintaining homeostasis in the body, it actually has detrimental effects on the body when the concentration of cortisol is at high and/or prolonged levels. Chronic stress can be attributed to high and prolonged levels of cortisol and can result in impaired cognitive function, suppressed thyroid function, blood sugar imbalances (ex. hyperglycemia), decreased bone density, decreased muscle tissue, increased blood pressure, decreased functionality of immune system, increased fat, and swelling due to inflammatory responses in the body.
Scott, Elizabeth. “Cortisol and Stress: How to Stay Healthy.” About.com Stress Management. N.p., n.d. Web. 04 Nov. 2013. <http://stress.about.com/od/stresshealth/a/cortisol.htm>.