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Scientists found a major clue why 4 of 5 autoimmune patients are women

February 1, 2024 at 11:02 a.m. EST
An X-ray scan shows bone and cartilage damage caused by rheumatoid arthritis, one of the autoimmune diseases more likely to affect women. (Bsip/Getty Images)
6 min

An international team led by scientists at Stanford University has discovered a probable explanation for a decades-old biological mystery: why vastly more women than men suffer from autoimmune diseases such as lupus and rheumatoid arthritis.

Women account for about 80 percent of the people afflicted with autoimmune diseases, a collection of more than 100 ailments that burden a combined 50 million Americans, according to the nonprofit Autoimmune Association. In simple terms, these illnesses manipulate the body’s immune system to attack healthy tissue.