There are numerous sources of stress but they boil down figuring out which of your stressors come from environmental, physiological and psychological sources.
Genetic based illness
Many diseases have a genetic component, some of which run in families. Examples include: alcoholism and schizophrenia.
Bacterial and Viral Disease
There are thousands of small critters running around which obey the biological imperative “to be fruitful and multiply” by attacking the host body that feeds them
The loss off a physical ability such as sight, mobility, speech etc. is extremely stressful.
Certain drugs such as alcohol and the opiates have dependency conditions that create painful withdrawal. Other drugs such as the central nervous system stimulates create a “down” after the “high.”
But for many, most of the stressors come from the environment.
Environmental Sources of Stress
Societal & Cultural
Certain things in the life of nations create stress for millions. These include recessions, war, political repression, etc.
Organizations periodically enter crisis periods which result in reorganizations, downsizing, plant and office closing, consolidations, and layoffs.
The Physical Environment
What for others are misfortunes are for him calamities. When their hog strangled on its tether, a laborer and his wife were desolate. The woman tore her hair and beat her head against a wall while the husband sat mute and stricken in a corner. The loss of the hog meant they would have no meat that winter, no grease to spread on bread, nothing to sell for cash to pay taxes, and no possibility of acquiring a pig the next spring. Such blows may fall at any time. Fields may be washed away in a flood. Hail may beat down the wheat. Illness may strike. To be a peasant is to stand helpless before these possibilities. — Banfield, E. C. (1958). The Moral Basis of a Backward Society. New York: The Free Press.
It can be hot enough to sweat or cold enough to shiver, too noisy, noxious orders can abound, the light is blindingly bright or frustratingly dim.
One winter’s day in 1659, a band of warriors from the Petun Indian village of St. Jean, south of Georgian Bay, went out to intercept an invading war party of Iroquois. They did not find the enemy. When they returned to the village, four days later, they saw only the ashes of their homes and the charred and mutilated bodies of many of their wives, children, and old men. Not one living soul had been spared from the flames. The Petun warriors sat down in the snow, mute and motionless, and no one moved or spoke for half a day, no one even stirred to pursue the Iroquois in order to save the captives or gain revenge. — Wallace, A. F. C. (1956). Mazeway disintegration: The individual’s perception of sociocultural disorganization. Human Organization, 16:23-27.
Most people have a nasty side.
Basically, too much to do in to little time Common complaint of managers everywhere. Numerous Deadlines. Only thing worse is changing deadlines
A 27 year-old asthmatic woman apparently died of cardiac standstill and did not exhibit asthma either before or during the interview. She had been reluctantly drawn into a discussion of her psychological problems, including the humiliation of a seduction, an illegitimate baby, and a rape attempt by her brother. As she recounted how she had been increasingly rejected by and cut off from her family and had to quit junior college and take menial jobs only to lose them because of asthmatic attacks, she became increasingly excited, cried, hyperventilated, and finally collapsed unconscious just as she was saying, “Naturally I always lost my job and had no hope anymore to recover. That’s why I wanted to die and want to die all the time, because I am no-good, no-good.” — Engel, G. L. (1971). Sudden and rapid death during psychological stress, folklore or folk wisdom? Annuals of Internal Medicine, 74:771-782
In 1985, the National Institute of Mental Health interview thousands of adults. Based on the interview, it was estimated that 19% of adults (36 million) suffer from a mental illness.
This type of illness is one that primarily originates from problems in thinking. For example, sometimes anticipatory stress comes from imagined catastrophes, uncertainty regarding the future. Such thoughts can lead to worry.
These class of illness originate primarily from problems and inability to deal with emotions. For example, depression is sometimes brought on by conditions of high anxiety.