A goiter is an enlarged thyroid gland, which is a butterfly-shaped
gland in the front of the neck. A goiter often causes a noticeable swelling in
the neck.
A goiter can be caused by a lack of iodine in the diet, a tumor or
nodule on the gland, a thyroid disease, or, rarely, cancer. In many parts of
the world, goiters are most common in people who have hypothyroidism, in which
the thyroid gland does not produce enough thyroid hormone, related to a
low-iodine diet.. In the United States, most people with goiters have chronic
autoimmune thyroiditis (Hashimoto's thyroiditis).
An enlarged thyroid may produce normal amounts of thyroid hormone,
or it may produce less- or greater-than-normal amounts. Treatment for a goiter
depends on the underlying cause.
