There is now evidence that points to abnormal stress responses as causing various diseases or conditions. These include anxiety disorders, depression, high blood pressure, and cardiovascular disease, certain gastrointestinal diseases, some cancers, and even the process of aging itself. Stress also seems to increase the frequency and severity of migraine headaches, episodes of asthma, and fluctuations of blood sugar in diabetics. There also is scientific evidence showing that people experiencing psychological stress are more prone to develop colds and other infections than their less-stressed peers. Overwhelming psychological stress (such as the events of 9-11) can cause both temporary (transient) and long-lasting (chronic) symptoms of a serious psychiatric illness called posttraumatic stress disorder (PTSD).
Conclusions about the effects of stress
Uncontrollable, unpredictable, and constant stress has far-reaching consequences on our physical and mental health. Stress can begin in the womb and recur throughout life. One of the pathological (abnormal) consequences of stress is a learned helplessness that leads to the hopelessness and helplessness of clinical depression, but in addition, many illnesses, such as chronic anxiety states, high blood pressure, heart disease, and addictive disorders, to name a few, also seem to be influenced by chronic or overwhelming stress.
Nature, however, has provided us with wonderful processes (mechanisms) to cope with stressors through the HPA axis and the locus coeruleus/sympathetic nervous system. Furthermore, research has shown us the biological processes (mechanisms) that explain what we all intuitively know is true—which is, that too much stress, particularly when we cannot predict it or control its recurrence, is harmful to our health.