The Effects of High Cortisol

Along with adrenaline, cortisol works to prepare your body for an emergency. Produced by your body's perception of stress or a threat, it alters several key body functions temporarily to increase your ability to act quickly and protect yourself. While cortisol serves a useful purpose in the short term, it can harm the body over time and in high levels.

Short-Term Effects

• As part of your body's reaction to an emergency, cortisol increases blood sugar, increases your brain's use of it, and makes available a greater number of the substances that repair body tissues, according to the Mayo Clinic.

  Cortisol also conserves your body energy by inhibiting functions you don't need in an emergency. It alters immune system responses and suppresses the digestive system, according to the Mayo Clinic. It also curbs the reproductive system and growth processes.

Memory Loss

• Stress hormones divert energy from the hippocampus, the part of the brain that makes memories. Long-term exposure to high cortisol levels--defined by the National Institutes of Health as more than 23 micrograms per decileter (mg/dl) of blood--therefore damages memory. Cortisol also interferes with neurotransmitters, the brain cells' chemical means of communication. This can prevent you from recalling memories you've already made, according to the Franklin Institute.

Drug-Induced Osteoporosis

• Cortisol and cortisol-like drugs (such as those used to treat skin conditions, asthma and arthritis) can cause your bones to wither in the long term. According to the Australian Better Health Channel, cortisol inhibits the function of bone cells and makes it difficult for the small intestine to absorb dietary calcium. This can cause drug-induced osteoporosis, a weakening of the bones that causes pain and increases a person's risk of fracture and other injury.

Heart Disease

• A stressed mind can cause an unhealthy heart, according to Harvard University researchers. Chronic high levels of stress hormones can numb the heart to the signals it uses to tell how much blood each part of the body needs. This can lead to severe disturbances in heart rhythm, including ventricular fibrillation. This is a deadly series of fast contractions of the heart's lower chambers. Stress hormones also lead to the production of chemicals that damage the lining of arteries. Psychological stress can make arteries rigid and restrictive to blood flow.

Degenerative Cycle

• High cortisol levels damage the hippocampus, which is part of the body's mechanism for shutting off cortisol production. The weaker the hippocampus, the less ability it has to tell the body to stop producing cortisol. In effect, chronic high cortisol levels cause chronic and even higher cortisol levels. The Franklin Institute refers to this as a "degenerative cycle" that is difficult to stop.