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All About Your Thyroid

Thyroid graphic

The thyroid is a butterfly-shaped gland that sits along the front of the windpipe below the Adam's apple. When it is not enlarged, the thyroid is difficult to feel through your skin.

The thyroid gland secretes thyroid hormones directly into the blood, distributing them to various tissues. Thyroid hormones regulate metabolism, body temperature, growth, development, and reproductive functions. They also help the brain, heart, muscles, and other organs working normally. So yes, the thyroid gland is an important organ.

Weight gain that is seen in severe and long-standing deficiency of thyroid hormones can be easily corrected. "A common misperception is that the thyroid is a root cause of weight gain in all subjects, but it usually is not," states Dev Abraham, MD, Director of Thyroid and Parathyroid Tumor Program with University of Utah Health.

Thyroid conditions affect an estimated 20 million Americans. Primary care doctors, family practitioners, nurse practitioners, or assistants perform blood tests to diagnose common conditions of the thyroid. Nodules within the thyroid gland are very common and do not affect thyroid gland function in most subjects. The vast majority of nodules are benign and are discovered by chance during scans performed in the region of the thyroid.


The main hormone that the thyroid secretes is thyroxine, also called T4. Hyperthyroidism is a condition that results from T4 overproduction. If it is mildly overactive, then there are generally no serious health consequences. The most important long-term effects of overactive thyroid gland are irregular heart rhythm and bone loss.

Hyperthyroidism has a number of causes. The most common cause is the autoimmune disorder Graves' disease, where the body creates an antibody that stimulates overproduction of T4. Other causes are less common. Grave's disease is treated using radioactive iodine in the form of a capsule that destroys the overactive portions of the thyroid. It is generally safe and the most common treatment throughout the U.S.


Symptoms of hyperthyroidism:

  • Fatigue or muscle weakness leading to difficulty lifting or climbing stairs
  • Increased anxiety
  • Rapid or irregular heartbeat
  • Insomnia
  • Weight loss
  • Increased frequency of bowel movements
  • Light or skipped menstrual periods



Underactive thyroid, also known as hypothyroidism, results from the deficiency of thyroid hormones. The most common cause is the painless and spontaneous destruction of the gland due to an autoimmune process called Hashimoto's disease. Other causes include surgery for thyroid cancer or treatment for an overactive thyroid. Hypothyroidism is treated by supplementing thyroid hormone, levothyroxine, in the form of a pill.

Unborn babies depend on their mother for thyroid hormone production, especially for the first 12 weeks. Low thyroid hormone levels during pregnancy can impair brain development in unborn babies. Therefore, it is particularly important for mothers to maintain optimal levels during pregnancy.

Symptoms of hypothyroidism:

  • Extreme fatigue
  • Depression
  • Forgetfulness
  • Stiffness or swelling in joints
  • Slower heart rate
  • Weight gain
  • Constipation
  • Heavy menstrual periods

If you experience symptoms of hyperthyroidism or hypothyroidism, see your family practitioner.