What is the Thyroid?
The thyroid is a small gland, shaped like a butterfly, located in the lower part of your neck. The function of a gland is to secrete hormones. The main hormones released by the thyroid are triiodothyronine, abbreviated as T3, and thyroxine, abbreviated as T4. These thyroid hormones deliver energy to cells of the body.
What Diseases and Conditions Affect the Thyroid?
The most common problems that develop in the thyroid include:
Hypothyroidism — An underactive thyroid.
Hyperthyroidism — An overactive thyroid.
Goiter — An enlarged thyroid.
Thyroid Nodules — Lumps in the thyroid gland.
Thyroid Cancer — Malignant thyroid nodules or tissue.
Thyroiditis — Inflammation of the thyroid.
When the thyroid gland is underactive, improperly formed at birth, surgically removed all or in part, or becomes incapable of producing enough thyroid hormone, a person is said to be hypothyroid. One of the most common causes of hypothyroidism is the autoimmune disease called Hashimoto’s disease, in which antibodies gradually target the thyroid and destroy its ability to produce thyroid hormone.
Symptoms of hypothyroidism usually go along with a slowdown in metabolism, and can include fatigue, weight gain, and depression, among others.
When the thyroid gland becomes overactive and produces too much thyroid hormone, a person is said to be hyperthyroid. The most common cause of hyperthyroidism is the autoimmune condition known as Graves’ disease, where antibodies target the gland and cause it to speed up hormone production.
Autoimmune Thyroid Disease
Most thyroid dysfunction such as hypothyroidism or hyperthyroidism is due to autoimmune thyroid disease. Autoimmune disease refers to a condition where the body’s natural ability to differentiate between its tissues, organs and glands, vs. outside bacteria, viruses or pathogens, becomes disrupted. This causes the immune system to wrongly mount an attack on the affected area, by producing antibodies. In the case of autoimmune thyroid disease, antibodies either gradually destroy the thyroid, or make it overactive.
Sometimes the thyroid becomes enlarged — due to Hashimoto’s disease, Graves’ disease, nutritional deficiencies, or other thyroid imbalances. When the thyroid become enlarged, this is known as a goiter.
Some people develop solid or liquid filled cysts, lumps, bumps and tumors — both benign and cancerous — in the thyroid gland. These are known as thyroid nodules.
A small percentage of thyroid nodules are cancerous. While thyroid cancer is a rare cancer
When the thyroid becomes inflamed, due to bacterial or viral illness, this is known as thyroiditis. There are a number of types of thyroiditis .