Are autoimmune diseases more common in men or in women?

There is currently no concrete proof of this sexual variation in autoimmune diseases.

The sole passive theory offered states that while estrogen consistently tends to strengthen the immune system, testosterone has a tendency to suppress it.

Thus, in reverse, we can say that as estrogen boosts immune system, so antibody production is also enhanced, which is a major drawback of the immune system in these patients suffering from autoimmune diseases. Men therefore tend to suffer more from infectious diseases, whereas women suffer less from them.

Hashimoto's thyroiditis, for instance, is an autoimmune disease that affects women more frequently than men by a factor of 20. Similar findings have been made regarding SLE, ulcerative colitis, Crohn's disease, rheumatoid arthritis, and other conditions that also exhibit a female preponderance.

Autoimmune diseases are more common in women than in men.