What does the thyroid gland do?

Stephanie Smooke-Praw, MD
Endocrinology Diabetes & Metabolism
The thyroid gland is responsible for producing thyroid hormone (T4 and T3), which is involved in regulation of metabolism, bowel function, heart rate, temperature sense, menstrual regularity, and other functions. The thyroid is controlled by the pituitary gland in the brain. The pituitary gland produces thyroid stimulating hormone (TSH), which controls the secretion of hormone from the thyroid gland.
The role of the thyroid gland is to make, store and release thyroid hormones. These hormones have a large impact on your health as they are involved in many important cell functions. This includes everything from growth of the body and brain, to the release of other important hormones, and even how energized you feel. The thyroid is so important that it has a special communication system with the brain in order to make sure that the correct amount of hormone is being made and released.
Julia Schlam Edelman
OBGYN (Obstetrics & Gynecology)
The thyroid is a soft, butterfly-shaped gland located in the neck, in front of the trachea (windpipe). The thyroid gland regulates metabolism, telling the body how fast to think and move and process food and waste. Thyroid function affects hair health, including breakage, texture, rate of growth, and rate of loss. It affects nail health and growth. It affects reflexes (which may become too fast or too slow) and the quality of sleep.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Located at the base of the neck on both sides, the butterfly-shaped thyroid gland produces thyroid hormone after receiving chemical signals from the pituitary. The main function of the thyroid hormone is to regulate the metabolism of your cells-that is, the chemical changes in your cells that cause them to live, grow, and die.

You can think of your metabolism a little bit like your utility bill. From neighbor to neighbor, no two utility bills are alike. Some people keep their AC at 76; some keep it at 68. Some take 20-minute showers; some hop in and out in 20 seconds. We all use and consume energy a little bit differently in our homes, and we all use and consume it a little differently in our bodies. And that plays a key role in weight management; some of metabolism is genetic, in that you're pre-disposed to have a quick-working metabolism or a slow-churning one. That regulation comes in part from your thyroid hormone.
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YOU: The Owner's Manual, Updated and Expanded Edition: An Insider's Guide to the Body that Will Make You Healthier and Younger

Between your full-length mirror and high-school biology class, you probably think you know a lot about the human body. While it's true that we live in an age when we're as obsessed with our bodies as...
The thyroid gland uses iodine to produce thyroid hormones -- primarily thyroxine (T4) and triiodothyronine (T3). T4 gets converted into T3 (a more active form) in the blood. Thyroid hormones regulate our metabolic rate and affect weight and energy level. The thyroid also produces calcitonin, which contributes to calcium balance. Thyroid hormone production is regulated by a feedback system involving the pituitary gland (a small gland at the base of the brain).
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Background: What is the thyroid?

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A member of our endocrine system, the thyroid gland produces hormones that help control many of our body functions, such as weight and temperature.Located at the base of our neck, this butterfly-shaped gland makes several hormones...

, which are collectively known as thyroid hormones. These hormones are especially key in the brain development of infants and children. Thyroxine, also known as T4, is the primary hormone secreted by the thyroid gland; this hormone helps control our metabolism, a chemical process that turns our food into energy. A lack of iodine in your food can cause the thyroid to swell, a condition called a goiter. Several other disorders and diseases can affect this gland, including cancer. If you notice swelling in your neck or feel a lump, make sure you see your doctor; this could indicate a problem with this important gland.

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.