- Education and Science»
- Life Sciences
Facts about Thyroid Disorders - Hyperthyroidism & Hypothyroidism
The thyroid gland produces hormones that are responsible for the proper functioning of the body system.
Thyroid hormones are essential for the proper growth and metabolism of the body. They directly affect the functioning of most of the organs in the body.
Thyroid disorders occur when the thyroid gland does not produce the right amount of hormones that are needed by the body.
To fully understand thyroid disorders, let us have a look into the structure and function of the thyroid gland.
Structure of the Thyroid Gland
The thyroid gland is a small bow shaped gland that sits in front of the windpipe right below the larynx also known as the voice box. The thyroid gland has two lobes located on either side of the windpipe connected by a narrow strip of connective tissue called “isthumus”.
Hormones Produced by the Thyroid Gland
The three hormones produced by the thyroid gland are -
- Thyroxine (T4)
- Triiododthyronine (T3)
The main hormone produced by the thyroid gland is the “Thyroxine” hormone also referred to as T4. Once Thyroxine enters the blood stream a small amount of the hormone is converted into “Triiododthyronine” that is also referred to as T3.
Calcitonin is another hormone produced by the thyroid gland. Calcitonin reduces calcium levels in the bloodstream when the concentration of calcium is above the normal level.
The brain plays an important role in the proper functioning of the thyroid gland. When the thyroid hormone levels are low, the brain produces a hormone called, “Thyrotropin Releasing Hormone” also referred to as TSH. TSH stimulates the thyroid gland to produce more T4 when T4 levels are low.
Importance of Iodine
The main component of thyroid hormones is iodine. Iodine is very important for the proper functioning of the thyroid glands. Iodine cannot be produced by the body; it has to be absorbed from the nutrients that enter the blood stream while digesting food.
Functions of the Thyroid Gland
The thyroid gland is responsible for the following functions in the body -
- maintaining the body temperature
- heart beating properly and the strength of the pulse
- proper utilization of food
- proper growth of the brain in children
- overall growth in children
- the quick response of the nervous system
What is Hyperthyroidism - Causes and Symptoms
Hyperthyroidism is a condition in which thyroid hormones in the blood are above the normal level. Hyperthyroidism occurs when there is an increase in the production of the thyroid hormone, thyroxine.
A condition called Grave’s Disease is responsible for most hyperthyroidism conditions. Grave’s Disease occurs when the body fights against and attacks the thyroid gland. The thyroid gland responds to the attack by producing more thyroxine. When this happens, the thyroxine level in the blood shoots up above the normal level.
Sometimes hyperthyroidism can be because of a swollen thyroid gland or small growths in the thyroid gland called nodules.
- sudden weight loss
- the rapid increase in heartbeat
- nervousness, anxiety
- excess sweating
- menstrual irregularities
- experience difficulty in sleeping
- hair becomes thin and brittle
- enlarged thyroid gland (goitre)
There are medications to cure hyperthyroidism. Hyperthyroidism can be life-threatening if it is not treated.
What is Hypothyroidism - Causes and Symptoms
Hypothyroidism is a condition that occurs when thyroid hormone levels in the blood are low. Hypothyroidism occurs when the thyroid gland does not function properly and produce enough thyroid hormones.
The main cause of hypothyroidism is a condition called, "Thyroiditis". In this condition, the thyroid gland is swollen, inflamed and does not produce enough amounts of thyroid hormones for the body to function properly.
Hypothyroidism can also be due to Hashimoto’s Disease, a condition in which the body attacks the thyroid gland and destroys it.
Other causes of hypothyroidism are -
- effect of certain medication
- birth defects
- surgical removal of a part or the whole thyroid gland
- pituitary tumor or surgery
- treatment with radioactive iodine
Hypothyroidism may include the following symptoms -
- extreme sensitivity to cold temperatures
- dry skin
- puffy face
- increase in weight without reason
- muscle weakness
- muscle stiffness and aches
- swelling of joints
- slow heart beat
- irregular or heavy menstrual periods
When hypothyroidism is not treated, it may lead to a condition called myxoedema. Myxoedema occurs in advanced stages of hypothyroidism and can be life threatening. Myxedema can lead to decreased blood pressure, decreased breathing and decreased body temperatures.
There are tests to detect thyroid conditions. Medications are available for treatment of thyroid disorders.