Cortisol is a steroid hormone that is made naturally in your body. It is secreted by the adrenal glands located on top of the kidneys. When we perceive a threat or stressor, our bodies react within seconds to allow us to handle the situation or escape to safety. Although cortisol is best known as a stress hormone, it participates in blood pressure regulation, glucose metabolism, immune function, nutrient metabolism, mental alertness, and provides increased energy.
When cortisol is released during the Fight or Flight response, the body responds by increasing glucose availability to the brain, heart, and large muscles (critical organs in the stress response).
Cortisol secretion varies among individuals. One person may secrete higher levels of cortisol than another, although responding to the same call.
Cortisol is naturally released in higher amounts in the morning and declines throughout the day. For people who work night shifts, this pattern can reverse. First responders who experience abnormal sleep patterns in the course of a shift can secrete cortisol throughout the day and at night.
While small increases of cortisol have beneficial effects, too much cortisol in the bloodstream can cause a variety of health problems: high blood sugar, anxiety, depression, fatigue, gastrointestinal upset such as constipation, bloating, or diarrhea, increased abdominal fat, diabetes, headache, heart disease, high blood pressure, lowered immunity, decreased inflammatory response, irritability, memory and concentration problems, sleep difficulties, weight gain, and slow recovery from exercise. Due to the fact that First Responders are subject to increased cortisol release, it is important to be aware of these negative symptoms.