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Thyroid Disease 101: The Basics
from Mary Shomon,
your Guide to Thyroid Disease

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.
This Thyroid 101: All About Your Thyroid article has more in-depth information to help provide an overview of the thyroid. And if you are wondering if you might have one of these thyroid conditions, take an interactive self-test online: Quiz: Could You Have a Thyroid Problem?.

Hypothyroidism

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.

Hyperthyroidism

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.

Goiter/Thyroid Nodules

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.

Thyroid Cancer

A small percentage of thyroid nodules are cancerous. While thyroid cancer is a rare cancer, it's on the rise. Learn more about thyroid cancer in these articles:


Thyroiditis

When the thyroid becomes inflamed, due to bacterial or viral illness, this is known as thyroiditis. There are a number of types of thyroiditis:



Treatments Some people don't feel well, even after treatment. If you fall into this category, you're probably frustrated, but there are solutions. Try some of the 10 Ways to Feel Better with Thyroid Disease. And be sure to read My TSH Test Results Are Normal, But I Still Have Symptoms.

Doctors for Your Thyroid Treatments

It's important to find the right doctor for your thyroid care, and to work effectively with that practitioner. An endocrinologist is a specialist in endocrine disorder, including thyroid disease. But you'll want to know: Do you really need an endocrinologist?

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