What is hypothyroidism?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
If you’re constantly freezing, your thyroid might be to blame! Watch Dr. Oz explain the function of your thyroid and how to tell if hypothyroidism is affecting your extremities.
Marjorie Nolan Cohn
Nutrition & Dietetics

Hypothyroidism (underactive thyroid) is a condition in which your thyroid gland doesn't produce enough of the thyroid hormone. Hypothyroidism can also be secondary if it is caused by a lack of thyroid hormone secretion due to inadequate secretion of thyrotropin (thyroid-stimulating hormone [TSH]) from the pituitary gland or thyrotropin-releasing hormone (TRH) from the hypothalamus (secondary or tertiary hypothyroidism). Whether it’s primary or secondary, the symptoms are the same.

Dr. Michael Roizen, MD
Internal Medicine
When your thyroid underproduces (hypothyroidism), your pituitary gland secretes extra thyroid-stimulating hormone to try and goose it into action. Eventually, your thyroid grows so large that you see a large lump (or goiter) on the front of your neck.

Some experts don't even treat a mildly underactive thyroid. But get your cholesterol tested; even a middling thyroid problem increases your risk of cholesterol problems and heart disease. Talk to your doctor about continued thyroid testing.
Celeste Robb-Nicholson
Internal Medicine
The tiny butterfly-shaped gland, the thyroid, influences virtually every organ system in the body. The hormones it secretes into the bloodstream play a vital role in regulating metabolism -- the rate at which our bodies convert food and oxygen to energy. Low thyroid hormone production, or hypothyroidism, causes a range of symptoms -- fatigue, constipation, dry skin and brittle nails, aches and pains, and feeling down -- that you might easily attribute to other health problems.

Untreated hypothyroidism can increase your risk for high cholesterol, high blood pressure, and heart disease. But it is easily diagnosed with a blood test and treated with a pill. That's why it's important to keep an eye out for the symptoms and have your thyroid function checked.
Hypothyroidism is a thyroid problem in which the thyroid is underactive or non-active. It is more often seen in women than men. In general, hypothyroidism can be diagnosed by a thorough history and blood tests. Hypothyroidism is most commonly caused by an underlying thyroid disease (primary hypothyroidism) instead of a problem with TSH production (secondary hypothyroidism). The most common causes of primary hypothyroidism are autoimmune thyroiditis (Hashimoto's thyroiditis or lymphocytic thyroiditis), surgical removal of the thyroid (thyroidectomy), radioactive iodine treatment, certain medications, and exposure of the neck to significant radiation.
Hypothyroidism is a condition in which the thyroid gland does not produce enough of certain hormones.  Symptoms may vary and may increase in severity if left untreated.

Hypothyroidism results when the thyroid gland produces too little thyroid hormone. The thyroid is a gland located at the base of the neck below the voice box. It is about two inches long and is shaped like a butterfly. Its purpose is to produce thyroid hormones, which regulate the body's metabolism. Hypothyroidism can slow down several bodily functions.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.