The immune system is unique. It consists of a team including white blood cells, organs, chemical mediators, and antibodies, which collectively try to safeguard the body from foreign invaders that may occur in cells or in the blood.
In addition, while the immune system is very efficient at removing these invaders, including bacteria, viruses, or cancer cells, it can become compromised because of external interference, in this case chronic stress.
Acute stress is not harmful to the immune system, but long-term stress has a way of suppressing the immune system so that it does not react in the method it was supposed to.
Here are some specific ways chronic stress affects the immune system:
Reduces Nutrient Uptake
Many people do not realize this, but a very large part of your immune system resides in your intestines and gut. These consist of the goof probiotic bacteria, which make here, home, and promote metabolism of the food we eat along with keeping not so desirable microbes at bay.
Cortisol, apart from suppressing the action of the bacteria, also causes nutritional deficiencies by speeding up movement of food. The faster food passes through the intestines, the less time it spends for active nutrient recovery to occur.
This alone has far-reaching implications for the entire body as a whole, since without sufficient nutrients for recovery to ensue, you are leaving your body wide open to attacks from the myriad of microbes we come into contact with every day.
In worst-case scenarios, it may require parenteral nutrition to ensure nutrients actually enter the blood.
Cortisol Resistance Leads to Enhanced Inflammation
This must be understood as it is a common misconception- cortisol by itself is an anti-inflammatory hormone. This is why the prescription based corticosteroid medications are used in conditions that have active inflammation, as they are all synthetic versions of the prototype- cortisol.
However, when this hormone is present in blood for durations that are too long to be considered normal, the body compensates by producing more pro-inflammatory compounds. In turn, cortisol’s effects are suppressed, but not the repercussions of its actions on the immune system.
Cortisol Promotes Insulin Resistance and Development of Diabetes
While the connection may not seem obvious at first, blood sugar levels do have an impact on immunity overall. For one, having high blood glucose levels chronically causes damage to a range of cells in the body, including nerves and to blood vessels. This in turn, impairs the ability of the immune system to properly detect and then remedy any pathogens that may be involved in the situation.
Cancers are More Likely to Develop
Every single day, under normal conditions, your body destroys multiple cells that have the potential of turning cancerous, without you ever realizing what’s going on. In particular, the body produces natural killer cells (or NK cells), which are specific for these cancer cells and do a good job of keeping you safe.
However, chronic stress levels suppress production and recruitment of this cell type, so that abnormal cells may keep growing trouble free. When they are detected, the cells are unable to get rid of them in a timely manner and full blown cancer develops.
Chronic Stress Desensitizes the Brain
Part of the way the immune system functions so precisely is due to a series of back and forth messages with the brain. However, similar to the way pain killers work, cortisol suppresses the chemical mediators that tell the brain what is going on, literally placing a blindfold on it. At first, the brain is still able to maintain relative normalcy, but under chronic stress these impulses may be blocked, causing no signals to be transmitted.