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]
What is hypothyroidism?
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•Last Updated: May 16, 2025
Hypothyroidism is a chronic condition characterized by low levels of thyroid hormone. If left untreated, hypothyroidism can lead to serious complications.