Immune System Function
Immune system function is linked to circulation and hydration, and therefore to valve system function. A large component of immune response takes place in the fascia, which is a type of connective tissue that surrounds all muscles, bones and organs, and connects different parts of the body together, providing structure and coordinating movement. The initial immune system defense mechanism is a more generalized response in which the area of infection is isolated and attacked in the fascia. In order for this component of immune system function to work, the fascia must be well-hydrated, and this is compromised during stress (as discussed in the blood circulation and hydration section), which can result in a weak immune system response.
Stress also affects the more specialized immune system response, in which the body creates a defense specifically designed for a certain type of invading organism. A class of stress hormones called glucocorticoids represses the function of the T cells and B cells responsible for creating this defense. Glucocorticoids can also remove these cells from circulation, as well as destroy them. In this way, prolonged stress results in a decrease of this specialized immune response. This is discussed in more detail in Robert Sapolsky’s book Why Zebras Don’t Get Ulcers, referenced on my recommended reading page.
Glucocorticoids also cause shrinking of the thymus gland, which produces T cells. In fact, this is one of the symptoms that first caught the attention of Hans Selye, pioneering researcher on stress as a generalized survival response.
By reducing stress and increasing activation of the parasympathetic nervous system, circulation and hydration increase and glucocorticoid levels decrease, which can strengthen immune system function.