Thyroid FAQs
Thyroid Overview
The thyroid is an organ that is considered part of the endocrine, or hormone system. It is located in the neck below the Adam's apple. The thyroid's main purpose is to produce thyroid hormones. These hormones then travel through the body in the bloodstream to all the other tissues and organs to help control metabolism.
- The thyroid is shaped like a butterfly. The two "wings" of the
butterfly are the right and left lobes of the thyroid. The connection
between the wings is called the isthmus.
- The two hormones that the thyroid produces are thyroxine (T4) and tri-iodothyronine (T3).
Location and picture of the thyroid gland.
Note two lobes of the thyroid, similar to butterfly wings.
- The thyroxine (T4) and tri-iodothyronine (T3) hormones regulate your body's metabolic functions such as heat
generation, and the utilization of carbohydrates, proteins, and fats. In
children, thyroid hormones are responsible for growth and development.
- The thyroid's production of T4 and T3 is controlled by regulatory
hormones from different parts of the brain. In the pituitary gland,
thyrotropin-stimulating hormone (TSH) is released and travels via the
bloodstream to the thyroid gland. TSH then stimulates the thyroid to produce
T4 and T3.
- The pituitary gland acts like a thermostat. When there is too much thyroid hormone in the bloodstream, the pituitary releases less TSH to signal the thyroid to produce less thyroid hormone. When there is too little thyroid hormone in the bloodstream, the pituitary releases more TSH to signal the thyroid to increase thyroid hormone production. Through this "feedback" system, the production of thyroid hormone is tightly controlled.
Picture of the Pituitary Gland
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Thyroid FAQs
Thyroid Problems Overview
The thyroid gland is located on the front part of the neck below the thyroid cartilage (Adam's apple). The gland produces thyroid hormones, which regulate body metabolism. Thyroid hormones are important in regulating body energy, the body's use of other hormones and vitamins, and the growth and maturation of body tissues.
Diseases of the thyroid gland can result in either production of too much (hyperthyroidism) or too little (hypothyroidism) hormone.
- Production of thyroid hormones: The process of hormone synthesis begins in a part of the brain called the hypothalamus. The hypothalamus releases thyrotropin-releasing hormone (TRH). The TRH travels through the venous plexus located in the pituitary stalk to the pituitary gland, also in the brain. In response, the pituitary gland then releases thyroid-stimulating hormone (TSH) into th...
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Thyroid Anatomy »
The thyroid is a brownish-red and highly vascular gland located anteriorly in the lower neck, extending from the level of the fifth cervical vertebra down to the first thoracic.
