The Thymus is a small gland located in the chest just under the breastbone.  The Thymus is critically important in the
body's response to disease invasion.  White blood cells originate in the bone marrow.  About half of them go directly
into the bloodstream and tissue fluids, but the rest of them must pass through the Thymus gland.  The Thymus gland
 is a central figure of the immune system because of its primary role in processing these white blood cells into
T lymphocytes.  These thymic lymphocytes carry out three defensive functions;  First, they stimulate the production
and growth of antibodies by other lymphocytes.  Second, they stimulate the growth and action of the phagocytes,
which surround and engulf invading viruses and microbes.  Finally, the thymus lymphocytes recognize and destroy
foreign and abnormal tissue.

The following are just some examples of the factors that can lower immune system efficiency and make one more
susceptible to all form of disease and illness:   alcohol, smoking, many prescription drugs, other drug use, high
cholesterol levels, excessive sugar consumption, allergies, chemical exposure, food additives, stress (physical,
mental, emotional), plus any other diseases or illnesses and many other external factors.