The immune system is involved in every part of the body and has evolved to protect against infections, foreign invasions, and signs of damage.

“Our immune system permeates almost every aspect of our health and disease. It is a system really in the sense of it it's involved in every part of our body that has evolved to protect us largely to protect us against infections, viruses, bacteria fungus. all sorts of foreign invasions and our immune system has developed a balance that is when it's working properly doesn't recognize the cells that are supposed to be in the body but is finely tuned to recognize signs of things that shouldn't be in the body and to eliminate them.”