What is thyroid disease?

The thyroid, a small gland located in the front of the neck, produces the hormones that regulate the speed of the chemical functions of the body -- its metabolic rate. When the thyroid gland is overactive (hyperthyroidism), too much hormone is produced and body functions speed up. This condition is believed to be caused by immune (protective) reactions of the body. On the other hand, when the thyroid gland is underactive (hypothyroidism), too little hormone is produced and body functions slow down.

Subclinical (symptomless) hypothyroidism occurs in 6% to 8% of adult women and in 3% of adult men. As with overt (symptomatic) hypothyroidism, the disorder occurs more frequently in the elderly and those with Down's syndrome. Subclinical hyperthyroidism occurs in 0.2% to 5% of the elderly and often resolves on its own.

Most patients with thyroid dysfunction will show symptoms within a few months of the start of the disease.

Suzy  Cohen

Thyroid disease occurs when the thyroid makes too much or too little thyroid hormone, T4. In this video, pharmacist Suzy Cohen, RPh, explains what happens when your thyroid can’t convert T4 to T3 properly, and what symptoms to look out for.

The thyroid gland is one of the major endocrine organs in the body, locate in the center of the neck just below the Adam's apple. The thyroid gland's main job is to control the body's metabolism. Thyroid diseases can be broken down into four major subgroups: thyroid nodules (masses in the thyroid), multiple nodules), diseases of thyroid function (hypo- and hyperthyroidism) and cancer. 

Thyroid disease encompasses a large variety of problems with the thyroid. The thyroid can be become underactive (hypothyroid) or overactive (hyperthyroid) for many different reasons. Blood tests are usually the first step in diagnosing thyroid disease. The thyroid can also become enlarged (goiter) or develop nodules (growths within the thyroid). Based on physical exam and blood tests your doctor can determine if other studies are needed such as ultrasound, thyroid scan, or biopsy and the appropriate treatment.

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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.