Stacey Colino has provided an excellent overview of the physio-pathological effects of stress on man. The prehistoric man reacted to danger in two ways: he fought or he fled. This made W,B, Cannon (1914) coin the term "fight or flight" response. Stress today has become a disease of the century. It effects all body systems, including the nervous, endocrine, gastrointestinal, and the immune system. This disturbs 'homeostasis', i.e.,the constancy of the internal environment in relation to external influences.
Hans Selye (1956), the propounder of the General Adaptation Syndrome (GAS) , described three fairly well defined stages of stress --- Alarm, Adaptation, and Exhaustion. In GAS primarily the hypothalamo-pituitary-adrenal axis operates to produce the anti-stress response through the hormones adrenaline and adrenocorticosteroids.
The three Fs -- fight, fright, and flight (the basic animal characteristics) almost cover our entire life.
Acute or occasional stress is protective in nature. Whereas, chronic stress shatters "adaptation" of the body leading to stress-related diseases. Almost 90 per cent of diseases today are psychosomatic in nature.
According to the Yerkes-Dodson Law 'mild stress' improves performance, whereas, 'severe stress' causes its deterioration. In a classical experiment Hans Selye injected croton oil under the skin of a large number of rats, which formed painful inflammatiory pouches. He found that the rats which were subjected to 'mild stress' healing was hastened.
Stress in a way lies in the eye of the beholder. Somebody has rightly said, "Two men look out from the same bars, one sees the mud, and one the stars". Here the two men looking through the same prison bars reacted differently. One was frustrated, while the other was inspired.
Thus our attitude decides whether the stress would make us "better or bitter". Chronic brooding over sorrows and insults, resulting in 'self pity' indicates a faulty 'adaptation' leading to diseases ranging from itch to insanity.
A good stress buster is -- Do not cherish exaggerated ideas about 'self' , and try to have a sane estimate of your capabilities. Living life at break neck speed invites disease.