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Category: Medical

Topic: Stress and Disease

Level: AEMT

8 minute read

GENERAL ADAPTATION SYNDROME is the predictable way the body responds to short-term and long-term stress, involving the nervous and endocrine systems, as described by the endocrinologist Hans Selye:

  1. The "ALARM STAGE" is the immediate reaction to a stressor—fight-or-flight response; also lowers immune system increasing susceptibility to illness.
  2. "RESISTANCE" (or, "ADAPTATION" STAGE): the body adapts to the stressors it is exposed to. Changes at many levels take place to reduce the effect of the stressor.
  3. "EXHAUSTIONPHASE": the stress has continued for some time, and the body’s resistance gradually decreases or collapses quickly. The body’s ability to resist disease may be almost entirely eliminated at this time—leading to heart attacks and hypertension, for example.

This stress triad includes our thyroid, adrenals and hormones (male of female). When stressed, thyroid function goes down, adrenal function produces too much cortisol, and testosterone or progesterone use is amplified.

The immune system, nervous system, and endocrine system play off of each other and work to develop the fight-or-flight response during stress.

Stress decreases the immune system’s ability to stave off illness and with prolonged stress, illness is much more likely. Excess stress can cause

  • heart attack,
  • muscle atrophy,
  • decreases in collagen in connective tissue,
  • respiratory compromise and illnesses,
  • depressed immune system,
  • GI problems like ulcers,
  • GU problems like kidney stones,
  • skin diseases and poor healing to wounds, depressed endocrine function, and
  • overall fatigue and depression.



CORTISOL is released from the adrenal cortex (the adrenals--or, suprarenal glands, on the tops of the kidneys).

Cortisol, as part of the fight-of flight-response, activates certain chemical changes within the central nervous system increasing reaction speed and dilation of the pupils.


  • stimulates glucogenesis and makes glycogen;
  • raises the free amino acids in the blood serum by inhibiting collagen formation, decreasing amino acid uptake by muscle, and inhibiting protein synthesis;
  • stimulates gastric-acid secretion and the excretion of ammonium ions by deactivating the renal glutaminase enzyme;
  • down-regulates the synthesis of collagen and muscle and is an important structural component of both;
  • reduces bone formation and reduces calcium absorption in the intestines;
  • raises blood pressure and increases cardiac contractility.

NOTE, re: Cortisol and pain:

Cortisol, as stated above, depresses the immune system. While this may sound bad, it actually is part of survival in that, acting as an anti-inflammatory, it allows action when needed (fight or hasty escape), even when injured. That is, with anti-inflammation, you won't feel injuries as much and can better physically respond to danger.  However, when stress continues, there reaches a point at which cortisol becomes pro-inflammatory, which contributes to lower thresholds for perceiving pain in those with chronic pain (which of course is a chronic stress). Chronic stress, such as PTSD, can create more chronic stress from amplified perception of pain, all in a vicious cycle. Translated, stress makes pain worse. 

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