The stress response is our “flight or fight” response designed to quickly respond to danger and literally can save our life. Cortisol does this and many other jobs to aide in human survival. Cortisol produced by the adrenal glands comes from a small almond shaped gland that sits on top of our kidneys. This gland also produces adrenalin, together they are responsible for producing a cascade of hormonal reactions that give us energy when we most need it and play a significant role in the maintenance of our nervous system.
When running from danger this wonderful hormone is released in small amounts to give us instant energy. However it is also released under any stressful situation. An intimate component of our sympathetic nervous system, small amounts of cortisol are released throughout the day when we are working hard and our nerves are ramped. When our system is continuously flushed with cortisol it is like driving with your foot stuck on the gas peddle, so even when you stop, the engine is continually running. Today’s stressors are constant and chronic and can keep cortical levels raised for days, weeks, even months.
How Cortisol works:
In order to increase energy, cortisol must quickly supply glucose into the blood stream to provide fuel for cells. It does this by triggering liver and fat cells mainly around the belly to release glucose. The release of glucose triggers an excess release of insulin necessary to drive glucose into cells for energy. Chronic stress and over stimulation delivers way more glucose than we need (especially since we are rarely being chased by tigers). These results are chronic increased heart rate, increased blood pressure, blood sugar imbalance, sleep disruptions and increased appetite. Furthermore, the excess glucose or sugar gets stored as fat. Visceral fat in hips and stomach is 4 times more sensitive to cortisol than subcutaneous fat, which lies under the skin. This means gain weight in our hips and belly disproportionally. In addition, this deregulation of glucose production and storage leads to muscle wasting because when we exercise our bodies will now choose to use muscle glucose from our extremities, such as arms and legs, rather than fat stores for energy.
Chronicly high insulin levels signal the brain to release the hormone gherlin which signals an increase in hunger while it inhibits the release of the hormone leptin which tells the body to stop eating. Without the release of leptin the brain gets the message that the body is starving so we eat more. The starvation response is designed to store more energy which means we create more fat.