Cortisol is produced in the body as a natural response to stress. The primary effect of cortisol is protection of the body during times of crisis. However, when chronic stress is present, it causes an over-production of cortisol. There are many negative effects of cortisol over-production, including memory loss, suppression of the immune system, and a shortened life span. Exhaustion of the gland that produces cortisol may also occur. This is called adrenal fatigue and results from a cortisol deficiency.
Memory loss is one of the effects of cortisol that apply to the brain. High cortisol levels have been shown to damage the hippocampus area of the brain, which is responsible for learning and memory. This can make it difficult for the brain to access an existing memory and lay down a new memory. For this reason, people often have a hard time answering questions after a crisis. They don't have access to some memories while the cortisol is affecting their brain.
Interestingly, cortisol also helps to form memories in times of crisis. With the help of adrenaline, cortisol burns emotionally charged memories into the brain. It serves a survival purpose to help a person avoid such stressful situations in the future.
When cortisol levels reach a high point, certain areas of the brain, including the hippocampus, send a message to stop cortisol production. Unfortunately, the hippocampus is sometimes too damaged by the cortisol to function properly, leaving the cortisol flowing and continuing destruction. This is one of the most difficult cortisol effects to reverse.
The effects of cortisol also include suppressing the body's immune system. The purpose of suppressing the immune system is to reduce inflammation in case an injury occurs during crisis. The reduced blood flow to the injury limits the pain experienced. This explains why after a car accident the victim usually doesn't feel the full impact of injury until after the crisis is over.
The weakened immune system also leaves the body much less defended against diseases and viruses. The cortisol effects place healing at a lower than normal priority. It has been shown that as few as 20 minutes of stress inhibits the immune system for up to three days.
Another example of the negative effects of cortisol is weight gain. When high cortisol levels occur in the body frequently, insulin is unable to function properly. This leads to an increase in blood sugar levels, which results in fat buildup in the abdomen. Excessive cortisol also affects the digestive system by causing too much gastric acid production in the stomach. This is a very common cause of heart burn.
The most significant of all the negative effects of cortisol might be that it literally shortens life. Not only does it increase blood pressure, but high levels of cortisol weaken the body's cells. The cells are then more susceptible to damage and age faster.
Too much cortisol also slows the production of collagen, which is essential to the entire body's structural support. Studies performed on rats show that skin tissue suffers the most collagen loss when exposed to high cortisol levels. Wrinkled and tired-looking skin are included in the many effects of cortisol.
