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Thyroid Facts

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 bloodstream to all the other tissues and organs to help control metabolism in adults and growth, development, and metabolism in children.

  • The thyroid is shaped like a butterfly. The two "wings" of the butterfly are the right and left lobes of the thyroid, with lie on both sides of the trachea or main breathing tube. The connection between the wings is called the isthmus.
  • The two hormones that the thyroid produces are L-thyroxine (T4) and tri-iodothyronine (T3).

Location and picture of the thyroid gland. Note two lobes of the thyroid, similar to butterfly wings.

Picture of the Thyroid Gland
Picture of the Thyroid Gland
Medically Reviewed by a Doctor on 7/31/2014
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Thyroid Diseases

What Are Thyroid Diseases and Problems?

There are many diseases and conditions of thyroid problems. Examples of thyroid problems include:

  • hypothyroidism (underactive thyroid),
  • hyperthyroidism (overactive thyroid),
  • hypothyroidism in pregnancy,
  • hyperthyroidism in pregnancy,
  • postpartum thyroid disease,
  • thyroid nodules,
  • goiter,
  • thyroid cancer,
  • Hashimoto's thyroiditis,
  • Graves' disease,
  • thyroid storm, and
  • myxedema coma.

Medscape Reference

Read What Your Physician is Reading on Medscape

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.

Read More on Medscape Reference »

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