How stress affects our immune system
Posted: 2016, September 9 | No Comments
Stress is thriving in our fast-paced society. It is omnipresent in every person’s life. How we learn to manage it can have profound effects on our health and well being.
But, why should we care about our immune system?
The reason is that it plays an important role in a variety of diseases. It protects us against infectious diseases, a cold or influenza for example, skin diseases, inflammatory and autoimmune diseases like rheumatoid arthritis, multiple sclerosis and also tumors depending of their type.
Many researches in psychoneuroimmunology have been done on the effect of stress on immune cells.
What is psychoneuroimmunology?
PNI is the study of the interaction between psychological processes and the nervous and immune systems of the human body. It is about how the brain talks to our immune system: the interaction between our psyche, brain, hormones and immune system.
Where are our immune cells located?
Cells of the immune system (white blood cells or leukocytes) are found all over our body. They are not only in our blood vessels but in the lymphatic vessels acting as their conduit, as well as in the immune organs like the lymph nodes (ex. in the neck), the thymus, liver, bone marrow, intestine etc… The gut is probably the organ having the greatest number of immune cells to fight against intrusive bacteria.
The release of stress hormones
Being exposed to stress circumstances, as you probably know, triggers the release of stress hormones like cortisol. Studies have shown that these stress hormones in the blood stream are immune suppressive.
It affects the white blood cells of diverse types (T cells, natural killer cells, cytokines) in their numbers. What we call cells traffic or trafficking is the way that the immune cells move in our body. And researches point out that the outpouring of stress hormones influences their distribution, also affecting their efficiency.
However, most of the immune fights take place in the lymph nodes and immune organs through a neural pathway, not the blood stream where we have to wait for a molecule to move slowly. The way it works is that the brain extends neural fibers to directly enter the immune organs right next to immune cells.
You probably already know for having experiencing it, that being under stress or having certain emotions of fear or anger, provokes an arousal feeling, often called a fight-flight reaction. What you may not know is that it activates these sympathetic fibers of the nervous system entering the immune organs. It then releases neurotransmitters, as norepinephrine hormones (NE) in close proximity to immune cells being present in the immune organs. And this release can also negatively alter the immune cells functioning.
There are then two ways stress by the activation of specific hormones react with immune cells:
– in the blood stream altering their distribution and activity
– through the sympathetic nerves directly entering the immune organs
Short term vs chronic stress
What is interesting to note is that researches have indicated that very brief stressors contrary to chronic stress enhance the immune system. It has been found that an immediate stressful circumstance, as in an environmental context, jumping of a plane for example has the immune cells function better. If a stressful event lasts a couple of days for example, it would not be true.
Do thoughts matter?
Remember when I previously mentioned psychoneuroimmunology, I stated that it also has to do with the interaction of our psyche with the immune system. This brings the question: Do our thoughts matter to our immune system?
The answer is YES. The brain is our conduit for affecting our body in response to different thoughts. It has been found in laboratory that the perception of controllability of a stressor negates immune impairment. Placebo response (i.e. taking a pill without the presence of medication) in eliminating symptoms of an illness is another example well documented of how the perception of a benefit can positively affect our health.
Our perception of our social situation also seems to affect our immune system. Social support predicts better health while bereavement, loss of social status, low social power, belonging to a stigmatized group (ex. being obese) are factors showing an increase of stress hormones and a decrease in immune cell functions.
What is driving our cortisol response is what is going on in our brain or what we perceive as happening, our social perception of the world.
Hypnosis is one beneficial solution
Managing our stress is very important. We just have to think of the proliferation of autoimmune diseases nowadays to realize how important it is that our immune cells function at their best. This is why we have to learn how to take care of ourselves, to have these moments of quietness and contemplation beneficial to our wellness. And again hypnosis is a powerful tool that can certainly help to achieve this goal.
One way to reduce stress is the practice of relaxation and even better, self-hypnosis. This could be a great subject for an upcoming blog.