Cortisol belongs to the main group of hormones known as stress hormones because their release is increased dramatically during physical or emotional stress. As cortisol pours into the bloodstream during episodes of stress, its action is on liver cells that convert fats, proteins, and stored glucose (known as glycogen) into glucose for additional release into the bloodstream. Again, this helps to prevent interruption in the supply of fuel the brain needs from the circulating glucose in the blood.
Cortisol’s action is to promote normal function of other body tissues by helping to regulate blood-glucose levels during either external environment changes or during fasting or starvation. Its heightened secretion occurs only under stress. Cortisol acts like a two-way light bulb. It displays a minimal amount of light normally, but it can immediately switch into a greater luminescence when more juice stimulates it.
Cortisol is manufactured in the adrenal cortex, an outer layer of the adrenal gland located above the kidney. Adrenal glands are paired, just as the kidneys are. They are physiologically known as endocrine glands. Endocrine glands are glands that produce hormones. The adrenal glands themselves are controlled by other regulatory mechanisms that reside within the brain. Cortisol and its counterpart, cortisone, both exhibit anti-inflammatory properties on body tissues. Their properties are simulated by cortisone or prednisone injections given by doctors for their patients suffering from rheumatoid arthritis or allergies. However, excessive levels of these natural or man-made hormones over long periods of time can contribute to unwanted conditions such as bone loss and a depressed immune system. Another unwanted condition of cortisol during stress is its ability to scramble our appetite control mechanism causing us to make poor food choices when we’re hungry. Its greatest effect on appetite is its association with serotonin, a significant messenger in the brain.
Continually excessive release of cortisol will reduce the brain’s ability to utilize glucose effectively. This creates two problems. First, it forces a person to eat increased amounts of sugar to try to offset this reduction. Secondly, free-radical damage occurs to brain cells as the cortisol exposure over time becomes toxic. This can interfere with memory and learning ability and can also increase anxiety. Elevated chronic levels of cortisol have also been associated with depression and weight gain.