Although doctors have at times dismissed a stress related complaint as being all in the patient's 'head', they were not far off the mark. A decade of research has demonstrated that sustained levels of stress and the resulting overproduction of cortisol, a stress hormone, can have severe effects on the hippocampus, a part of the brain involved in memory formation. High levels of cortisols have also been found to have links with post traumatic stress disorder.

WHAT HAPPENS WHEN YOU ARE STRESSED?
When you find yourself in a stressful situation, your body quickly reacts by releasing the hormone adrenaline into the bloodstream. Adrenaline elevates your blood pressure, tenses up your muscles and speeds up your breathing. In addition, energy is rapidly mobilized from storage sites. Glucose and the simplest forms of protein and fats come pouring out of fat cells, the liver and muscles. Why do you think these changes happen? Your body is preparing to cope with an immediate emergency. Once your body has mobilized all that glucose, it needs to deliver it to the muscles as quickly as possible, so the heart rate and blood pressure must increase too. Your breathing rate increase because to mobilize all that extra glucose, your muscles will need more oxygen.

This is known as the flight or fight response.

Less visible physiological changes also occur as a result of the stress response. The digestion slows, growth and reproduction are inhibited, and sexual drive decreases. Female are less like to ovulate or to carry pregnancies to term, while males begin to have trouble with erections and secrete less testosterone. The immune system is also inhibited. In other words, almost all longer term processes are suppressed, as energy is directed towards an immediate reaction to an emergency.

Finally, during stress, cognitive and sensory skills can become more acute. You may notice that certain aspects of memory improve and your senses become sharper temporarily. Again, these changes help you to cope more effectively with the immediate crisis.

THE DAMAGING EFFECTS OF STRESS
Psychological and social stress is a relatively new invention. Our stress reactions have evolved over million of years to help us cope with much more basic survival situations. In evolutionary terms, it is only the blink of an eye since humans lived as hunters, sprinting across the Savannah in search of prey, or to escape a hungry lion. We are extremely adept at coping with acute physical stresses of this kind - the flight or fight response outlined above is just what we need. We are also well designed to cope with chronic physical stresses, such as drought, famine, parasites. Few people reading this will ever experience this sort of stress, however, it is an everyday reality for many people living in third world countries.

When was the last time you experienced a flight or fight response?. What physical symptoms did you experience? Do you think this response helped you to deal with the situation or made it more difficult?.

Problems can arise because our body reacts to psychological and social stresses as if they were physicsal stresses. The result is that we often react to stress in ways that are inappropriate, unhelpful and harming. The flight or fight response, which is ideally suited to helping us escape a hungry lion, can be disastrous to our health because we switch it on for months at a time worrying about mortgages, relationships and promotions. We are in a state of chronic stress.

STRESS AND PHYSICAL ILLNESS
According to The American Institute of Stress, as many as 75 to 90 per cent of all visits to GPs are stress related. To cope with this complaints, Americans alone consume five billion tranquilizers, five billion barbiturates, three billion amphetamines and sixteen thousand tons of aspirin every year. Medical research is now showing strong connections between external factors such as diet, lifestyle and environment and our more serious diseases. We now take it for granted that high blood cholesterol, diabetes mellitus and cigarette smoking are high risk factors in heart disease. Yet in over half of the new cases of heart disease, none of these risk factors is present.

In a 1988 study by DR Hans Eysenek, he reported that unmanaged reactions to stress were more predictive of death from cancer and heart disease than cigarette smoking. In fact, in the aftermath of a heart attack, the greatest predictors of recovery are not physiological factors - such as arterial blockage or the condition of the heart itself - but emotional factors. A startling report discovered that job satisfaction and overall happiness are the factors most likely to determine a patient's recovery. A growing body of scientific evidence demonstrates the direct impact of emotional attitudes on health and well being.

What is happening to cause such serious damage?.

What we often do not always realize is that many illnesses only happen after something has been going wrong for a long period of time. The real ailment is not the final precipitating factor, it is what happen between good health and the disease.
Research has shown that the body's stress response involves over fourteen hundred known physical and chemical reactions and over thirty different hormones and neurotransmitters. In other words, every system in the body is affected by stress in some way or another, even organs such as the kidneys and the stomach, which one would not normally think is affected. Among the most important hormones activated under stress are adrenaline, noradrenaline and cortisol. Research has shown that even hours after the stress has subsided, levels of these hormones can remain high. Cortisol in particular, has been an important focus of research, because of the extensive role it plays in the body's response to stress. In balance amount, cortisol is essential for the healthy functioning of our bodies, but when levels rise to high, it can be extremely damaging to our system. When we are under stress and our bodies produce high levels of cortisol over long periods of time, the brain internal thermostat resets and directs the body to maintain a higher level of cortisol production, thinking that this is normal. Chronically elevated levels of cortisol have been shown to impair immune function, reduce glucose utilization, increase bone loss and promote osteoporosis, reduce muscle mass, inhibit skin growth and regeneration, increase fat accumulation, impair memory and learning and destroy brain cells. Chronic stress accumulates day by day, week by week, year by year. As noted earlier, for most people, it is the daily accumulation that does the most damage; the little stresses that add up to far more than the big jolts do. We adjust to everyday stress, but it is a totally unnecessary habit and the biochemical pounding that results takes its toll on our bodies.

We accommodate stress because we do not realize how serious the consequences are and because it has become so much a part of the routine that it feels normal to us. After all, are not our friends going through the same thing? When stress becomes chronic, our bodies do not have time to catch up everyday. Even if we pause for a few hours to give ourselves a little break from the onslaught, our body chemistry has been altered as surely as if we have taken a drug. It cannot just snap back into place again. After ten shots of whiskey, no cup of coffee is going to make you sober; you have to wait for the effects to subside - without drinking (or, in this case, stressing out) while you wait. We all have a stress threshold or crisis point, beyond which we become seriously ill. As we have seen, under mild pressure, the adrenaline and cortisol burst brought on by stress can lead to a temporary increase in performance, followed by a healthy fatigue that we can eliminate by resting. But with unrelenting adrenaline and cortisol arousal, our performance increasingly falls short of what we expect. Things start to go dramatically downhill.

ANXIETY
Anxiety - the long term distress caused by life pressures - has been shown in numerous studies to be a significant factor in the development of illness. When anxiety helps us to prepare for danger, then it is useful, but as we have seen in modern life, anxiety is often out of proportion and out of place. Distress comes in the face of situations that we must live with or that are conjured by the mind, not real dangers we need to confront. Repeated bouts of anxiety signals high levels of stress.

In a 1933 review in the Archive of Internal Medicine of extensive research on the stress disease link, Yale psychologist, Bruce McEwen, noted a broad spectrum of physical effects: compromising immune functions to the point that it can speed up the development of cancer, increasing vulnerability to viral infections, exacerbating plaque formation leading to arteriosclerosis and blood clotting leading to heart attacks; accelerating the onset of diabetes; and worsening or triggering asthma. Stress can also lead to gastrointestinal ulcers and irritable bowel syndrome, as well as numerous other gastrointestinal complaints. The brain is also susceptible to the long-term effects of sustained stress, including damage to the memory. McEwen notes 'evidence is mounting that the nervous system is subject to wear and tear, as a result of stressful experiences'.

Have you noticed how you are more likely to catch a cold or flu when under stress?.
There is now good evidence to show that when we are under emotional stress our normal body defenses fail, so we are no longer able to fight off viruses and other infections effectively. Sheldon Cohen, a psychologist working at a specialized colds research unit in Sheffield carefully assessed how much stress people were feeling in their lives and then exposed them to the cold virus. Not everyone who comes into contact with such a virus will catch a cold, indeed usually a robust immune system can fight it off. Cohen found that the more stress people have in their lives, the more likely they were to catch a cold.

A similar study of married couples showed how everyday hassles and upsetting events, such as marital fights, could affect the immune system. A distinct pattern emerged - three or four days after an especially intense batch of upsets, people often came down with a cold or upper respiratory infection. You now begin to see why stress have such a profound effect on health. The physical effect of mental stress and anxiety - the kind produce by high pressure job and high pressure lives are now well documented. Understandably, the health risks are greatest for those whose jobs are high in strain, in particular, jobs which demand a high level of performance while allowing the person little or no control over how the job is done.