What actually sets off an autoimmune disease?
Most autoimmune diseases start when a person with genetic susceptibility encounters an environmental trigger—often an infection, hormonal shift, toxin, or medication—that disturbs immune tolerance. The confused immune system then attacks normal tissues, and the process is reinforced by gut barrier leaks, chronic stress, and dysregulated hormones. The exact mix varies by disease, but research consistently shows a gene‒environment interaction rather than a single cause.