Thyroid Disease

What Is the Thyroid?

The thyroid is a small gland below the skin and muscles at the front of the neck, at the spot where a bow tie would rest. It's brownish red, with left and right halves (called lobes) that look like a butterfly's wings. It usually weighs less than an ounce.

What Does the Thyroid Do?

Though it's small, the thyroid does many important jobs, especially for teens. For instance, it:

makes the hormones that help control metabolism and growth
helps the body go through sexual development

What Do Thyroid Hormones Do?

Thyroid hormones are released from the gland and travel through the bloodstream to the body's cells. They help control the growth and the structure of bones, sexual development (puberty), and many other body functions.

By helping cells convert oxygen and sugar and other body fuels into the energy they need to work properly, these hormones are important in helping a child's body mature as it should.

Thyroid hormones also directly affect how most organs function. So a thyroid that isn't working as it should can cause problems in many other parts of the body.

What Are the Types of Thyroid Disease?

Thyroid disease happenss when the thyroid gland doesn't supply the proper amount of hormones needed by the body. This can cause:

Hyperthyroidism

If the thyroid is overactive, it releases too much thyroid hormone into the bloodstream. This is called hyperthyroidism. The body use up energy more quickly than it should, and chemical activity (like metabolism) in the cells speeds up. Graves' disease, an autoimmune disease, is the most common cause of hyperthyroidism.

Read more about hyperthyroidism and Graves' disease.

Hypothyroidism

If the thyroid is underactive, it makes too little thyroid hormone, causing hypothyroidism. The body uses up energy more slowly, and chemical activity (metabolism) in the cells slows down. Hashimoto's thyroiditis is an autoimmune disease that causes most cases of hypothyroidism in kids and teens.

Read more about hypothyroidism and Hashimoto's thyroiditis.

Goiters and Thyroid Nodules

Both hypothyroidism and hyperthyroidism can make the thyroid larger than normal. An enlarged thyroid gland is a lump that can be felt under the skin at the front of the neck. When it is large enough to see easily, it's called a goiter. A thyroid nodule is a lump or enlarged area in the thyroid gland.

Read more about goiters and thyroid nodules.