Over the past decade, extensive research has revealed how important the immune system is to the body's ability to resist acute and chronic diseases, and to function at its most effective level. We now recognize that even a healthy immune system can be affected both by our mental and emotional states, and by the body's own chemical mediators, i.e., lithium, noradrenaline and all the different zytokines.
Healthy human beings are equipped with 1.5 kilograms (3.3 pounds, cell count totaling more than 1012) of immune competent cells, which are the main component of that invisible organ, the immune system. These cells consist of a cocktail of macrophages including the white blood cells (T- and B lymphocytes) which are natural killer cells, and plasma cells. Furthermore, these individual cells of the immune system are linked to each other through constant chemical feedback from within the body in response to harmful intruding organisms.
The immune system also has a counter-mechanism that keeps its killer and scavenger cells from destroying normal healthy tissue and organisms. This counter-mechanism consists of the T-suppressor cells. Suppressor cells have the power to increase the body's ability to kill incompatible organisms and they work in conjunction with T-helper cells to balance immune system responses. The ratio between the suppressor and helper cells determines how powerful the body's self-defense system is at any given time. In healthy people, the normal ratio is 1.2 -