Medically reviewed by
Natalie Bessom, D.O. Board-certified family medicine doctor with specialty training in nutrition, USA
If you have been diagnosed with or know someone who has a thyroid condition you probably have come across at least one unfamiliar or confusing term. It’s important to understand, the basics at least, of what some of the most common thyroid terms mean.
We’ve put together a glossary of common thyroid terms associated with thyroid medical conditions that we’ve gathered from the American Thyroid Association and the British Thyroid Association. These will range from terms associated with but not limited to hypothyroidism, hyperthyroidism, thyroid cancer, goiters, and thyroid nodules.
Antibodies: Proteins in the blood that detect and destroy foreign bodies, such as viruses and bacteria. Auto-antibodies are antibodies that attack the body’s own tissues, such as thyroid cells, and cause Graves’ disease and Hashimoto’s thyroiditis.
Autoimmune disorder: A disorder where the body makes antibodies that attack its own normal cells and tissues, for example, autoimmune thyroid disease and diabetes.
Autoimmune thyroid disease: The body makes antibodies that attack its own normal cells and tissues, for example, Graves’ disease and Hashimoto’s thyroiditis.
Autoimmune thyroiditis: This is the most common form of hypothyroidism. The body’s immune system attacks the thyroid cells as though they were foreign cells, leading to hypothyroidism. This is also known as Hashimoto’s thyroiditis.
Endocrine gland: A gland that produces hormones.
Endocrinologist: A doctor specializing in diabetes and disorders of the thyroid, parathyroid and adrenal glands.
Goiter: A swelling of the thyroid gland.
Graves’ disease: An autoimmune condition that causes hyperthyroidism – an overactive thyroid. Graves’ disease is much more common in women than in men. It got its name from Robert Graves, an Irish physician who described patients with this condition in the 19th century.
Hashimoto’s thyroiditis/Hashimoto’s disease: Also known as autoimmune thyroiditis. This is the most common form of hypothyroidism. It is a disorder in which the body’s immune system attacks the thyroid cells as though they were foreign cells, leading to hypothyroidism.
Hyperthyroidism: An overactive thyroid gland. The T4 and/or T3 are raised and the TSH is low.
Hypothyroidism: An under-active thyroid gland. The T4 level is low and the TSH level is high.
Larynx: Adam’s apple
Levothyroxine: A synthetic form of the thyroid hormone thyroxine (T4) contained in medication to treat an under-active thyroid gland. It is one of the most popular thyroid medications.
Metabolism: The speed at which the body’s cells work to break down oxygen and calories to convert to energy. The speed is controlled by the thyroid gland. If there is not enough thyroid hormone, the cells work too slowly; if there is too much thyroid hormone, the cells work too fast.
Nodule: A lump (on the thyroid or in the neck area).
T3 (triiodothyronine): Another term for triiodothyronine, one of the hormones made by the thyroid gland.
T4 (thyroxine): Another term for thyroxine, one of the hormones made by the thyroid gland.
Thyroid eye disease (TED): An eye disease that is associated with Graves’ disease.
Thyroid-stimulating hormone (TSH): Hormone secreted by the pituitary gland that regulates the hormonal output from the thyroid gland. This hormone regulates the amount of T3 (triiodothyronine) and T4 (thyroxine) produced by the thyroid gland. Its measurement is used to confirm the diagnosis of hypothyroidism (raised TSH level) and of hyperthyroidism (depressed TSH level).
TSH Test: Measures the amount of TSH in the body. This test is often the most common and basic test used to determine a thyroid disease. It is, however, not considered a full test.
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Here at ThyForLife, we do our utmost to provide accurate information. If you require more detailed information regarding medical terms and conditions, please consult your healthcare provider. Always listen to the advice for your healthcare provider.