Goiters do not represent one disease. They can form quickly or very slowly over years. Before iodized salt was introduced in 1920, iodine deficiency was the main cause of goiter in the U.S., and it still is worldwide. In the U.S., the main causes of a goiter are (including Graves disease or Hashimoto's) and mutlinodular goiter. autoimmune disorders
Goiters can produce a normal amount of thyroid hormone, too much thyroid hormone ( ) or not enough thyroid hormone ( ). hyperthyroidismhypothyroidism