Vitamin D — Learn About Its Impact on the Immune System, Its Role in Autoimmunity, and Its Importance for Specific Autoimmune Diseases

Researchers have identified at least 80 different autoimmune diseases that affect at least 23.5 million Americans. The American Autoimmune Related Diseases Association, a nonprofit health agency whose mission is to eradicate autoimmune diseases and alleviate the suffering and the socioeconomic impact, believes both of these numbers may be too low and estimates there may be as many as 140 different diseases with a basis in autoimmunity. The organization also believes there may be as many as 50 million Americans with an autoimmune disease, as the 23.5 million estimate is based on only 24 autoimmune diseases. Whichever estimate is used, there appears to be no dispute that the prevalence is increasing.