Thanks to the advancement of medicine, life expectancy has increased significantly, but healthy life expectancy still lags behind. Immunity is a key factor that determines the healthy longevity.
Immune system is a shield of our body against pathogens externally and cancers internally. Immune dysregulation, which affects humans of all age, gives rise to various diseases such as allergic disease, autoimmune disease, gastrointestinal disease, cancer, atherosclerosis, and psychiatric problems such as depression and anxiety. Sometimes, it causes symptoms that does not conform to any established disease.