A weak immune system can lead to dysfunctions such as autoimmune diseases and tumors. An impaired immune system can, in fact, seriously affect one’s health. This is especially so in our modern world, where many pathogens have developed an increased resistance to antibiotics and antifungal medications.

Weakened immune function can manifest itself as a genetic or acquired immunodeficiency. The amount to which the immune system is compromised depends on the nature of the condition that leads to it and components of the immune system that are affected.

The immune system can be suppressed by such factors as emotional stress, such physical stressors as lack of sleep, physical over exertion, environmental chemical exposure, UV and other types of radiation, common viral or bacterial infections, drug therapies, blood transfusions or surgery.

A person’s eating habits can also affect the functioning of their immune system. Too much fat, alcohol and refined sugar along with too little protein, calories, vitamins, minerals and water can impair immune system function. Also after age 40, the biological process of aging tends to compromise immune system function.

Acquired infections or diseases (such as AIDS) can also weaken the immune system. Primary immunodeficiency diseases, such as Common Variable Immunodeficiency (CVID), are genetically determined.