Thyroid Gland

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The thyroid gland is a butterfly-shaped organ that is located at the front of the neck.

The thyroid gland produces three hormones:
  • Triiodothyronine, also known as T3
  • Tetraiodothyronine, also called thyroxine or T4
  • Calcitonin

Image result for thyroid gland


Here, the highlighted portion is the Thyroid Gland.





Hormonal output from the thyroid is regulated by Thyroid Stimulating Hormone (TSH) secreted from the Anterior Pituitary gland, which itself is regulated by Thyrotrophin-Releasing Hormone (TRH) produced by the hypothalamus.


The thyroid may be affected by several diseases. Hyperthyroidism occurs when the gland produces excessive amounts of thyroid hormones, the most common cause being Graves' disease, an autoimmune disorder. In contrast, hypothyroidism is a state of insufficient thyroid hormone production. Worldwide, the most common cause is iodine deficiency.




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