How Stress Affects Our Health

by Scott Morrice on 11/10/2011

I think we all understand that is important to understand how stress affects our health. I think we all recognize that stress has a very important role to play in the health of our mind/body. I know it certainly has in mine. Unfortunately, stress is a somewhat nebulous concept, and is therefore very difficult to define. For that reason conventional medicine has had a hard time responding to it. One of the problems is the many different specialties and areas of interest that are involved in stress research. Neuroendocrynology, autotonomic physiology, psychology, developmental biology, sociology, epidemiology—the list goes on and on. It all sounds incredibly complicated. And it is.

Having said that, and however complicated it may be, there seems to be ample evidence that the stressors in our life do cause illness. Unfortunately the “hows” of that are not so obvious.

Hopefully without getting too technical here, and relying heavily on the very readable explanation provided by Dr. Bruce H. Lipton in his book The Biology of Belief, an important aspect in all of this appears to be the role our hypothalamus-pituitary-adrenal (HPA) axis plays.

The HPA axis is the body’s first line of defense against external threats. When the body’s nervous system first perceives a threat, and perception is an important concept that I will come back to later, the hypothalamus secretes a hormone (CRH) which travels to the pituitary gland causing it to release yet another hormone (ACTH) into the blood. The ACTH, in turn, travels on to the adrenal gland and signals it to secrete the “fight or flight” adrenal hormones. The “fight or flight” hormones coordinate the function of the body’s organs, providing us with the power to deal with the perceived danger.

One of the first things to happen is that the stress hormones released into the blood cause the blood vessels of the digestive system to constrict. This forces blood to the body’s arms and legs, an action that allows us to move out of the way quickly. However, before this redirection, the blood was in the internal organs of the body, and depriving these organs of this supply of blood means the life-sustaining work of digestion, absorption, excretion and the production of the body’s energy reserves is compromised.

The body’s second line of defense is its immune system. And when the HPA axis swings into action in an effort to conserve energy reserves, it also puts a damper on the body’s immune system.

As if this weren’t enough, the HPA axis also interferes with our ability to think clearly. The processing of information in the forebrain, the centre of reasoning and logic, is much slower than the hindbrain, the centre of reflexive action. It is the latter action centre that is needed the most upon the happening of an event that is dangerous to the body, and so the stress hormones act to restrict the supply of blood to the forebrain in favor of an increased supply to the brain’s reflexive action centres. As well, these same hormones repress activity in the prefrontal cortex of the brain, the centre of conscious volitional activity, thereby reducing conscious awareness and intelligence. So, when you get frightened, you get dumber!

Unfortunately, in the world that we live in we are bombarded with all sorts of things to worry about, a very few of which deal with our survival, but most that do not. As a result, our body’s nervous system is constantly, but unnecessarily, having to deal with perceived threats. For a lot of us, our HPA axis is always switched “on” and our bodies are dealing with stress hormone levels that are consistently elevated.

This has its consequences. Dr. Lipton makes the statement in his book that almost every major illness that people acquire has been linked to chronic stress. Dr. Lee Pulos, in his CD series “The Biology of Empowerment: How to Program Yourself to Succeed at a Cellular Level” opines that, yes, life’s stresses do cause illness. And though he doesn’t believe that we create our cancers or other illnesses, he believes that if we don’t listen to our bodies, a part of us “allows” an illness to develop.

One of the keys, for me, in all of this, is that it is the body’s reaction to a perceived threat that initiates the resulting cascade of internal messages. In other words, perception is very important here. And I want to further explore some of the ramifications of that realization in a later blog.

  • Helen

    I have been assessed as suffering from adrenal fatigue and it is a long road to recovery. I using a number of alternative therapies to help heal from it including nutritional supplements, rest, exercise, meditation, massage and Reiki.

  • Anonymous

    This entry contains a great deal of truth; consequently, it has considerable potential to enrich the lives of its readers. It would be fally to reduce ourselves to the level of vegetative or animal life, life totally subject to sap or blood flow and hormonal secretions, imobile, involuntary, irrational life without capacity for thought, reason, and free choice. For that reason, I commend your insistence on the capacity of the human being to allow or not to allow the surrendor of perception.
    On a personal note, I must share with you my observation that the relaxation and stress-relief provided to a dying friend of mine by techniques such as those you mention made her passing more meaningful than it would have been otherwise.

    • Anonymous

      Thank you for your comments. As I said in the post, our perception of what is “out there” threatening us plays such an important role in all of this. There is much more to say on this issue, and I do want to come back to this at a later time.

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