What is Hashimoto’s Thyroiditis?

Hashimoto’s thyroiditis, also called chronic thyroiditis, is named for the Japanese doctor who discovered it. It affects about 5% of the adult population, increasing particularly in women as they age. Hashimoto’s, the most common form of thyroiditis, is the leading cause of hypothyroidism.

Hashimoto’s thyroiditis results from problems with the body’s immune system. Normally, the immune system defends against germs and viruses, but in diseases such as Hashimoto’s, the immune system attacks the body’s own tissues. In patients with Hashimoto’s thyroiditis, the immune system produce antithyroid antibodies, which damage the gland and keep it from producing enough hormones.

Diseases of the immune system tend to run in families and are about five times more common in women than in men. Hashimoto’s is linked to other autoimmune conditions, such as Graves’ disease, premature gray hair, diabetes mellitus, arthritis and patchy loss of pigment of the skin (vitiligo).