What causes a weakened immune system?

The stress can from different sources, emotional, lack of sleep, poor nutrition or disease.

Stress causes the body to pull its resources or depleted resources out of maintaining the immune system. The immune system becomes weakened by not being maintained.

Emotional stress can cause the body to fight depression rather than diseases. Emotional stress can lead to the development of cancers as the the mutated cells are not identified and destroyed before the cells begin to multiply out of control.

A lack of sleep also creates stress on the body. During the sleep cycle the body repairs itself. Without sleep the body can not repair itself leading to the weakening of the immune system.

The immune system uses proteins and vitamins to produce the antibodies and white blood cells needed to fight infections. Without proper nutrition the immune system is weakened. Vitamin C for example has a vital role in fighting infections like the flu and the common cold.

Fighting diseases put a strain on the immune system. A virus infection often weakens the immune system so that the virus infection is followed by a bacterial infection. AIDS is a virus that actually attacks and destroys the immune system.

Eat healthy, get lots of sleep, pray or meditate to relieve emotional stress, find relationships that are emotionally supportive, and above all avoid stress. ( It also helps not to get sick)