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- The Role of the Thyroid Gland
About Thyroid Disorders
The Role of the Thyroid Gland
Location and size
The thyroid is located in the front of the neck, just below the Adam’s apple. It is shaped like a butterfly with its wings spread, and wraps around the trachea. From top to bottom, the thyroid is 4 cm long and weighs about 20 g. It is a thin and soft organ. If there is no swelling, the thyroid is difficult to find by touch. However, if it swells slightly, you will be able feel it in your neck with your fingers. If the thyroid becomes larger, the swelling can be identified visually.
Thyroid function
Various types of hormones are produced in the human body, such as estrogens, androgens, and corticosteroids.
Organs that produce hormones are called endocrine organs. The thyroid is one of the endocrine organs and produces hormones from iodine contained in food, such as seaweed.
What are thyroid hormones?
Proteins, fats, and carbohydrates consumed in food are metabolized and used as materials to make body tissues and as sources of energy for the body to move. Thyroid hormones stimulate and facilitate these metabolic processes. In addition, thyroid hormones also play an important role in fetal development and child growth.
There are two types of thyroid hormones: thyroxine (T4) and triiodothyronine (T3). T4 contains four iodine atoms while T3 contains three iodine atoms.
The thyroid primarily synthesizes T4, which is then converted to T3 in the liver. T3 is an active hormone.
Role of the pituitary gland
The body has a mechanism for maintaining stable thyroid hormone levels in the blood. This mechanism is controlled by thyroid-stimulating hormone (TSH) which is secreted by the pituitary gland at the base of the brain. TSH works to stimulate the thyroid and promote the secretion of thyroid hormones T4 and T3.
When thyroid hormones (T4 and T3) are in excess in the bloodstream, TSH secretion from the pituitary gland is suppressed, thereby reducing the secretion of T4 and T3. In contrast, when blood levels of T4 and T3 are low, TSH secretion increases to promote the secretion of T4 and T3. This feedback mechanism maintains T4 and T3 levels within a proper
