Stress can be caused by hunger, thirst, work, psychological pressures or a multitude of other things. Stress is an unending aspect of life. However, most stresses are relatively easily confronted. For example, if you are hungry, you eat. Thus you restore your bodily balance and temporarily reduce that stress.
Stress is a normal part of everyone's life.
The effects of extreme stress were first systematically studied by Dr. Hans Selye, a physiologist from the University of Toronto. The GAS has three overlapping stages - alarm, resistance, and exhaustion. The first response to a strong stressor is alarm. Heartbeat and breathing quicken, muscles tense, and other physiological changes occur to cope with the stress. As body defenses stabilize, the symptoms of alarm seem to disappear.