• Conditions InDepth: Hypothyroidism

    The thyroid gland is a butterfly-shaped gland in the front of the neck. Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormones. A healthy thyroid produces the hormones thyroxine (T4) and triiodothyronine (T3), which control metabolism. This affects how many calories you burn, how warm you feel, how much you weigh, and how the body handles functions of the cardiovascular, gastrointestinal, and nervous systems. Hypothyroidism results in a slower metabolism and a slower heartbeat.
    The Thyroid Gland
    Copyright © Nucleus Medical Media, Inc.
    Hashimotos thyroiditis occurs when the immune system produces antibodies that attack cells of the thyroid gland. This results in thyroid swelling. Other less common causes include hypothyroidism as a result of neck radiation for lymphoma and treatment of hyperthyroidism or thyroid cancer with radioactive iodine or surgery.
    Other causes of hypothyroidism include:
    • Subacute thyroiditis —This occurs when there is inflammation of the thyroid gland after a viral upper respiratory tract infection.
    • Drugs —Drugs used to treat hyperthyroidism such as lithium (used to treat certain psychiatric disorders), certain cardiac medicines, and other medicines (interleukins, alpha interferon).
    • Medical treatments —Treatments include radiation or surgical removal of part of the thyroid gland (called subtotal thyroidectomy) to treat other thyroid diseases.
    • Idiopathic thyroid atrophy —The thyroid tissue shrivels up (atrophies) for unknown reasons.
    • Iodine deficiency —The thyroid gland does not get enough iodine to produce thyroid hormone (this is rare in the United States).
    • Iodine excess —Certain foods (such as shellfish) and certain medicines (such as cough medicine) contain large amounts of iodine, which can block thyroid hormone production (rare).
    • Infiltrative illnesses —Cancers and certain infections.
    • Pituitary adenoma —A benign tumor of the pituitary gland that can cause a problem signaling the thyroid to make thyroid hormones.
    • Postpartum thyroiditis —This condition usually improves but may be long lasting.
    • Congenital hypothyroidism —An infant that is born with problems making normal amounts of thyroid hormones.
    About 5% of Americans have hypothyroidism. This condition usually occurs in adults. However, in some cases, children or infants may have hypothyroidism (called cretinism ). Children need treatment as quickly as possible or intellectual disability may result.
    What are the risk factors of hypothyroidism?What are the symptoms of hypothyroidism?How is hypothyroidism diagnosed?What are the treatments for hypothyroidism?Are there screening tests for hypothyroidism?How can I reduce my risk of hypothyroidism?What questions should I ask my doctor?Where can I get more information about hypothyroidism?


    Garber JR, Hennessey JV, et al. Clinical update. Managing the challenges of hypothyroidism. J Fam Pract. 2006;55:S1-8.

    Hypothyroidism. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated November 19, 2012. Accessed November 20, 2012.

    Hypothyroidism. National Endocrine and Metabolic Diseases Information Service website. Available at: http://endocrine.niddk.nih.gov/pubs/Hypothyroidism/. Updated February 27, 2012. Accessed November 20, 2012.

    Vanderpump MPJ, Tunbridge WMG, et al. The incidence of thyroid disorders in the community: a twenty-year follow-up of the Whickham survey. Clin Endocrinol. 1995; 43:55.

    Revision Information

  • LiveWell personal health survey

    How healthy are you really? Find out – free.Learn more

    It's time to stop guessing. If you want to make some changes but just aren't sure how, the free personal health survey from LiveWell is a great place to start.

  • HeartSHAPE Spotlight

    At risk for a heart attack? Learn more

    Fight heart disease and prevent heart attacks. HeartSHAPE® is a painless, non-invasive test that checks pictures of your heart for early-stage coronary disease.

  • Calories and Energy Needs

    Calorie NeedsLearn more

    How many calories do you need to eat each day to maintain your weight and fuel your physical activity? Enter a few of your stats into this calculator to find out.

  • Ideal Body Weight

    Ideal Body WeightLearn more

    Using body mass index as a reference, this calculator determines your ideal body weight range. All you need to do is enter your height.

  • Body Mass Index

    Body Mass IndexLearn more

    This tool considers your height and weight to assess your weight status.

  • Can we help answer your questions?

    Wellmont Nurse Connection is your resource for valuable health information any time, 24 hours a day, seven days a week. Speak to a Nurse any time, day or night, at (423) 723-6877 or toll-free at 1-877-230-NURSE.