What is hypothyroidism?

Hypothyroidism is a chronic disease that occurs due to low levels of thyroid hormone. If hypothyroidism is not treated, long-term complications can cause debilitating disease and even death. In the U.S., autoimmune thyroid disease (Hashimoto’s thyroiditis) is the most common cause of hypothyroidism. However, globally, insufficient iodine intake is the most common cause of hypothyroidism.^[1]