Hypothyroidism Causes and Risk Factors | Hashimoto's Disease and More

Hypothyroidism - Causes and Risk Factors

The more common causes of hypothyroidism include the following:

Hashimoto’s disease: This "autoimmune" or "self-attacking-self" disease occurs when the body's immune system mistakenly attacks thyroid cells and damages them. Over time, the thyroid gland fails, which leads to hypothyroidism
Radioactive iodine treatment: Often when treating hyperthyroidism with radioactive iodine, a condition associated with excessive thyroid hormone production, hypothyroidism is the goal
Thyroid operation: Previous thyroid surgery can result in hypothyroidism, especially if most of the thyroid gland has been removed
Medication: Some medication such as amiodarone and lithium may cause hypothyroidism
Subacute thyroiditis: Subacute thyroiditis causes a painful inflammation of the thyroid and a period of hyperthyroidism as the damaged cells leak their hormone supply into the bloodstream, but this is followed by a period of hypothyroidism
Congenital hypothyroidism: A baby may be born with an insufficient amount of thyroid tissue or other health problems that do not allow for normal thyroid hormone production

While rare, hypothyroidism can also be caused by problems in the pituitary gland, the “master hormone gland” that controls the thyroid gland.