The term perceived threat makes an important distinction and brings up a critical point to remember: as in the case of chronic stress, the body's stress response is repeatedly triggered on a daily basis in response to actual physical and psychological threats as well as perceived psychological threats. As a result, the body can become exhausted, and the overabundance of epinephrine and cortisol, as well as other aspects of the body's stress response can become maladaptive, resulting in lowered immunity and other health problems. (Read this article for more on the effects of stress.)
Another important thing to remember about epinephrine and the body's stress response is that it can be triggered in response to negative stress as well as excitement or eustress. While eustress, or 'positive stress' can help maintain vitality, it's still important to maintain balance in how much your stress response is triggered, and to avoid too much total stress.
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