There are several causes and types of goiters. In some cases, the cause of goiter is unknown, and in others there can be a hereditary component. The entire gland may be enlarged (diffuse goiter) or the gland may have one or more nodules. Some of the more frequent causes are listed below.
A simple endemic (colloid) goiter may be caused by a lack of iodine in the diet, but this is rare in the United States. It is more common in underdeveloped countries where people lack iodine in their diets. In people with iodine deficiency, the thyroid gland does not produce enough hormones and an overproduction of TSH occurs that causes the thyroid gland to enlarge.
Graves Disease is an autoimmune disorder in which the thyroid gland produces too much T4 causing the thyroid gland to enlarge.
Hashimoto’s Disease (Chronic Lymphocytic Thyroiditis)
Hashimoto’s Disease is an autoimmune disorder that causes thyroid gland inflammation and enlargement. Irregularities in thyroid hormone production cause the pituitary gland to produce too much TSH.
Thyroid cancer is not very common. It frequently appears as an enlargement on one side of the thyroid.
Human chorionic gonadotropin (HCG) produced during pregnancy may cause a slightly enlarged thyroid gland.
Thyroiditis causes inflammation and enlargement of the thyroid gland. It may cause an over or underproduction of thyroid hormones. Thyroiditis may cause the thyroid gland to feel painful. The pain may increase with swallowing or pressure.
The prescription medication lithium can create changes in thyroid function that lead to goiter.