• Decrease font size
  • Default font size
  • Increase font size

Damage Caused by the Hormone "Cortisol"
By Dr. Neil Nedley

As previously stated, the increase of sev­eral hormones in the blood stream are in­volved in protecting us from a sudden stres­sor. One of these hormones is cortisol. However, ongoing high levels of cortisol caused by chrome and excessive stress can wreak havoc upon the body, causing much physi­cal and psychological damage. A list of damaging effects related to brain functions appears in Figure 6.

Impaired memory, item 6, refers to one's verbal declarative memory (recalling names, telephone numbers, etc.). Similar memory impairment may arise in individu­als who use cortisone-type medications for medical conditions. A case in point: chil­dren who take prednisone for asthma.

Item 7, shrinkage of the brain, can be caused by prolonged increases in cortisol levels. This takes on great importance for elderly individuals, or even those of younger age who may sense that their mental acuity is slipping. More effective strategies to manage stress without cortisol substances may slow the decline in memory performance. High cortisol levels damage the body in other ways. Some of them are listed in Figure 7.

Other damages caused by high cortisol

Item 7 in the figure is suppression of the immune system. Excess cortisol in the blood stream tends to weaken the immune system in two ways. First, it elevates blood sugar levels, which is a known detriment to the immune system. Second, cortisol it­self weakens the ability of certain white blood cells to kill bacteria.

A study related to the immune system revealed that higher than normal cortisol levels are linked to a decreased survival time in women with advanced breast cancer. These women had fewer and less powerful natural killer cells in their blood, and thus had impaired resources with which to at­tack the cancer.

In a classic study of medical students, the stress of taking exams resulted in a de­crease of certain white blood cells in the blood stream. When a stressor is perpetu­ated for days or weeks, as in the case of bereavement, the beleaguered immune sys­tem may be more susceptible to infectious diseases or cancer.

Another interesting study related to the immune system looked at two groups of workers who experienced a change in jobs. The first group voluntarily quit their job and found work elsewhere. Those in the second group were laid off and were forced to find another one, which was a stressful experience. The second group showed a greater risk of lung cancer.

Research makes one thing clear—per­sistent stress has profound effects on our immune system. Cancer is typically present for months or years before diagnosis. Thus, a weakened immune system produced by persistent stress increases our risk of serious problems long before a cancer is diagnosed.

Stress Increases Risk of Heart Dis­ease and Stroke

There are many studies indicating a strong connection between stress and artery blockage. Heart disease continues to be the leading cause of death in our nation. Grow­ing insights into its connections with stress cannot be ignored. The relationships are remarkable both for individuals who have never had problems with their heart and for those suffering from known heart problems. The evidence indicates that stress may not only increase the risk of a heart attack, but failure to effectively deal with stress can also lead to worse outcomes in the aftermath of a heart attack.  Several studies that demon­strate the connection ate recorded in Fig­ure 8.


 Duke University researchers studied 132 patients with heart disease. Normal every­day negative emotions such as tension, sad­ness, and frustration were found to double or triple the risk of significant decreases in blood supply to the heart muscle.

Likewise, it was noted that positive emo­tions, such as feeling happy and in control, were associated with a lower risk of reduced blood supply to the heart muscle. The Duke researcher demonstrated that even the low levels of ordinary stress that we experience may decrease blood supply to the heart.

As shown in Figure 8, programs that teach cardiac patients how to manage stress can reduce the occurrence of artery block­age. Dr. James A. Blumenthal of Duke University in Durham, North Carolina, and colleagues there and elsewhere studied a group of patients with coronary artery dis­ease (CAD) and documented artery block­age during mental stress testing. Patients that were instructed in the methods of man­aging stress had far less cardiac events than those who did not take the program. Dr. Blumenthal concluded that instructions in ways to manage stress are a very important part of cardiac rehabilitation, extending the health and life of individuals involved.

The Dutch investigators in Figure 8 analyzed 37 studies that examined results of cardiac rehabilitation programs that in­cluded instructions in stress reduction. They found positive effects on blood pres­sure, cholesterol, body weight, smoking be­havior, physical exercise, and eating habits, along with a 34 percent reduction in car­diac mortality and a 29 percent reduction in recurrence of heart attack.

When it comes to stroke, the basic un­derlying disease process is very similar to heart attack. Both disease states are char­acterized by blockage in blood vessels sup­plying vital organs. As expected, stress in­creases the risk of stroke.  In a group of Finn­ish men age 42 to 60, those who had the greatest stress-induced blood pressure increases showed the greatest amount of blockage in their carotid arteries.  Studies linking stress to blockage in neck arteries have implications beyond that of stroke risk. Such blockage is viewed as an indicator of the extent of blockages throughout the body, including ar­teries feeding the heart and other vital lo­cations.

Sudden stressors do not affect all people equally, according to research performed at Ohio State University. Researchers falsely accused participants of shoplifting, and then gave them five minutes to defend them­selves. The stressor was equal in intensity for each participant. All knew that their defense speech was being videotaped and judged. Those subjects with a. family his­tory of heart disease demonstrated greater el­evations of total and LDL cholesterol'(two cardiac risk factors) in response to this stress­ful experience.

Sudden mental stress not only increases cardiac risk factors like blood pressure and cholesterol; it also increases the risk of dan­gerous—and even life-threatening—heart rhythm problems. Research performed at Yale University found that, among predis­posed individuals, stressful emotions can provoke certain potentially fatal heart rhythm problems.

When comparing the effects of sudden mental stress with that of chronic or ongo­ing stress, it is found that chronic stress is also devastating to cardiac health. As previ­ously mentioned with respect to lung can­cer, lack of control over one's work situation has been linked with chronic stress in many studies. This predictor of chronic stress load also impacts heart health. A study of British government workers found those who felt they had little or no control over their job had lower blood levels of heart-protective HDL cholesterol. Some researchers believe that hormones such as adrenaline and cortisol may be directly con­tributing to the adverse cholesterol patterns occurring as a result of stress.

As with sudden stress, a decrease in HDL is not the only cholesterol abnormality associated with chronic stress. Total cho­lesterol also tends to rise under the influence of perpetuated stresses. Researchers have dem­onstrated that individuals with a family his­tory of heart disease have a greater tendency for their cholesterol to rise in response to stress.

We have examined some of the evidence linking stress with immune impairment, cancer risk, and heart disease. However, there are many other conditions that may be triggered by stress and its effect on weak­ening the immune system as outlined in Figure 9.


Each of these maladies deserve a closer look. The first on the list is herpes

Stress and Herpes

            Once someone is exposed to the herpes virus, it sets up lifelong residence in the ner­vous system. Prolonged exposure to stress can increase the risk of an outbreak of this pain­ful genital state. In one six-month study, researchers in San Francisco studied 58 women ages 20 to 44, all with a history of the recurrence of visible genital herpes. High levels of anxiety and persistent stress predicted the recurrence of herpes. Inter­estingly, the researchers found no connection with short-term stressful experiences


Depression the Way outFrom the book
Depression, the Way Out,
Nedley  Publishing, Ardmore, OK, 2001


Neil Nedley, M.D.,
Nedley Health Solutions
P. O. Box 1565
Ardmore, OK 73402


Toll-free: 1-888-778-4445
Phone: 1-580-226-8007
Fax: 1-580-223-2645