Fully 20 percent of the American population, or 50 million Americans, develops an autoimmune disorder. By some estimates, 75 percent are women, with conditions like rheumatoid arthritis, lupus, Crohn’s disease, and irritable bowel syndrome (IBS)—each terrible, frustrating, debilitating, hard to diagnose. Together, autoimmunity is the third most common disease category in the United States (after cardiovascular disorders and cancer).
