The thyroid gland is a small, butterfly-shaped gland located in the base of the neck just below the Adam's apple. Although relatively small, the thyroid gland plays a huge role in our body, influencing the function of many of the body’s most important organs, including the heart, brain, liver, kidneys and skin. Learn more about causes, symptoms, tests, diagnosis and treatments for thyroid conditions.

An underactive thyroid, or hypothyroidism, occurs when the thyroid gland creates less than the normal amount of thyroid hormone. The result is the “slowing down” of many bodily functions. Hypothyroidism usually is a permanent condition that can be treated. Learn more about the causes, signs, symptoms, tests, and treatments for hypothyroidism.

You can perform a simple Neck Check self-exam to help with early detection and check for lumps or enlargements in the neck that may point to a thyroid condition. Here is a step-by-step guide.

Hyperthyroidism occurs when the body makes too much thyroid hormone. This disorder occurs in almost one percent of all Americans and affects women five to ten times more often than men. Learn more about the causes, signs, symptoms, tests, and treatments for hyperthyroidism.

Hashimoto’s thyroiditis (also called Hashimoto's disease or chronic lymphocytic thyroiditis) is the most common thyroid disease in the United States. It is an inherited condition that affects over 10 million Americans. It is about seven times more common in women. Hashimoto’s disease involves the production of immune cells and autoantibodies by the body’s immune system that can damage thyroid cells and compromise their ability to make thyroid hormone. Hypothyroidism occurs if the amount of thyroid hormone produced is not enough for the body’s needs. The thyroid gland may also enlarge, forming a goiter.

Graves' disease is an autoimmune disorder which causes the immune system to overstimulate the thyroid gland and produce too much thyroid hormone. Learn about the causes, symptoms, diagnoses, and treatment options of Graves' disease.

Thyroid eye disease is a rare disease, typically associated with Graves’ disease (a cause of overactive thyroid), characterized by progressive inflammation and damage to the tissues around the eyes. Learn more about the causes, symptoms and treatment options.