How does stress affect the body?
Stress activates brain areas responsible for the regulation of internal organ function. The nervous system affects the immune system by sending signals to the lymph nodes, nerve plexuses, the thymus and the spleen. Plus, the endocrine system also produce hormones that affect immune cells. All of this generates an endless circle. Nature did not intend for a person to live in a constant state of stress. As a result, the body gets exhausted and is subjected to various diseases. Because the constant activity of hormones in the adrenal cortex inhibits the activity of immune system cells, the body's resistance to infectious diseases is weakened.
Causes of chronic stress can be external and internal factors: life problems, lack of sleep, fatigue and an unhealthy lifestyle in general.
Stress is a set of non-specific adaptive (normal) reactions of the body to the impact of various adverse factors – stressors (physical or psychological) that violate its homeostasis, as well as the relevant state of the nervous system (or the body as a whole).
Mechanisms of a negative impact on the immune system
Lymphocyte activation. Is accompanied by fever. Stress actually strengthens the immune system, not weakens it. The only problem is that nature conceived this effect as short-term. With constant stress exposure, the immune system reserves get depleted, entailing immunodeficiency.
Increased activity of the adrenal cortex. It releases cortisol, which is also called the stress hormone. This hormone is a glucocorticoid. It inhibits the immune system, and over time its excessively high level entails muscle atrophy and bone demineralization.
Improper regulation of internal organ functions. They are constantly stimulated, which eventually leads to functional disorders (diarrhea, abdominal pain, heartburn, palpitations, etc.).
The most important mechanisms of stress destructive effect on the human immune system are the following: