Thyroid disease is common, with approximately 20 million Americans having some type of thyroid disorder. The American Thyroid Association claims that up to 60 percent of people with thyroid problems are unaware of what is causing their symptoms. January is National Thyroid Awareness Month, a time to become aware of how the thyroid works and how it can influence the function of other important organs.
What Is the Thyroid and What Does It Do?
The thyroid gland is a small butterfly-shaped organ located in the front of the neck that wraps around the trachea (windpipe). It produces hormones that control the body’s metabolism and regulates many of the body’s vital functions, including how fast calories are burned and how fast the heart beats. If the body produces too little thyroid hormone, hypothyroidism can result. Too much thyroid hormone can result in hyperthyroidism. Both are serious conditions that need treatment.
The specific hormones the thyroid creates are called the T4 (thyroxine) and T3 (triiodothyronine) hormones. A properly functioning thyroid maintains the right amount of these hormones to keep the body’s metabolism working correctly. The pituitary gland, located in the center of the skull, monitors and controls the amount of hormones the thyroid produces.
Thyroid diseases include the following:
- Goiter: an enlargement of the thyroid gland
- Hyperthyroidism: when the thyroid gland produces more hormones than the body needs; the most common thyroid disorder
- Hypothyroidism: when the thyroid gland produces not enough hormones than the body needs
- Thyroid cancer
- Thyroid nodules: lumps in the throat
- Thyroiditis: swelling of the thyroid
Who Is at Risk for Thyroid Disease?
Thyroid diseases can affect males and females of all ages, from infants on up. Risk factors include: 
- Having a family history of thyroid disease
- Having an autoimmune disease, such as type 1 diabetes, lupus, or rheumatoid arthritis
- Taking medication that is high in iodine
- Being older than 60 and being female
- Having had treatment in the past for a thyroid condition or cancer
The Causes of Thyroid Disease
Both hypothyroidism and hyperthyroidism can be caused by other diseases that impact the functioning of the thyroid gland.
Conditions that can cause hypothyroidism include:
- Thyroiditis: an inflammation of the thyroid gland
- Hashimoto’s thyroiditis: an inherited autoimmune condition in which the body’s cells attack and damage the thyroid
- Postpartum thyroiditis: a temporary condition affecting from 5 percent to 9 percent of women after childbirth
- Iodine deficiency: a condition that hampers the production of thyroid hormones
- A nonfunctioning thyroid gland: a condition from birth
Conditions that can cause hyperthyroidism include:
- Graves’ disease: the entire thyroid gland might be overactive
- Nodules: nodules are overactive within the thyroid
- Thyroiditis: a temporary condition in which the thyroid releases hormones that were stored there
- Excessive iodine: too much iodine can cause the production of more thyroid hormones than it needs
Common Symptoms of Thyroid Diseases
Symptoms of hypothyroidism include:
- Fatigue
- Weight gain
- Puffy face
- Forgetfulness
- Dry or coarse hair
- Dry skin
- Thinning hair
- A hoarse voice
- An intolerance to cold temperatures
- Irregular and heavy menstrual periods
- Depression
- Slowed heart rate
Symptoms of hyperthyroidism include:
- Anxiety, irritability, and nervousness
- Trouble sleeping
- Weight loss
- An enlarged thyroid (a goiter)
- Muscle weakness and tremors
- Fine, brittle hair
- Feeling sensitive to heat
- Vision problems or eye irritation
- Irregular menstrual periods or the cessation of the menstrual cycle
- Rapid heartbeat and/or irregular heartbeat
- Nervousness
- Tremor
Thyroid Disease and Pregnancy
Hormones produced during pregnancy raise thyroid hormone levels in the blood. These thyroid hormones are necessary for brain development of the fetus. Because of the change in hormone levels during pregnancy, it is difficult to diagnose thyroid disease during pregnancy. Consider a thyroid screening before becoming pregnant since uncontrolled hypothyroidism and hyperthyroidism can present problems to the baby and mother.
Hypothyroidism during pregnancy can cause the following:
- Premature birth
- Preeclampsia
- Thyroid storm (a sudden, severe worsening of symptoms)
- Fast heart rate in the baby
- Low birth weight
- Miscarriage
Hyperthyroidism during pregnancy can cause the following:
- Anemia
- Preeclampsia
- Low birth weight
- Miscarriage
- Stillbirth
- Issues with growth and brain development in the baby
Diagnosis and Treatment
Thyroid diseases are diagnosed through blood tests, imaging tests, and a physical exam. Blood work will test for the following: 
- thyroid-stimulating hormone (TSH)
- T4
- FT4 (free thyroxine)
- T3
- FT3 (free triiodothyronine)
- Thyroid antibodies
- Calcitonin
- Thyroglobulin
Treatment can include the use of radioactive iodine, beta blockers, surgery, anti-thyroid drugs for hyperthyroidism, or thyroid-replacement medication for hypothyroidism.
More Information
For more information on thyroid disease, talk to your doctor, especially if considering becoming pregnant. Online information can be found at MedlinePlus, the Office of Women’s Health, and the American Thyroid Association websites.
Herrick Resources on Thyroid Diseases
The following resources can be requested and checked out by curbside pickup:
- 100 Questions & Answers About Thyroid Disorders, by Warner M. Burch
- The Cleveland Clinic Guide to Thyroid Disorders, by Mario Skugor and Jesse Bryant Miller
- The Complete Thyroid Book, by Kenneth Ain and M. Sara Rosenthal
- The Everything Guide to Thyroid Disease, by Theodore Friedman and Winnie Yu Scherer
- Thyroid Disease: Understanding Hypothyroidism and Hyperthyroidism, by Sandra Sardella White
Sources: Cleveland Clinic, Thyroid Disease, https://my.clevelandclinic.org/health/diseases/8541-thyroid-disease; Mayo Clinic, Hyperthyroidism (Overactive Thyroid), https://www.mayoclinic.org/diseases-conditions/hyperthyroidism/symptoms-causes/syc-20373659; Mayo Clinic, Hypothyroidism (Underactive Thyroid), https://www.mayoclinic.org/diseases-conditions/hypothyroidism/symptoms-causes/syc-20350284; MedlinePlus, Thyroid Diseases, https://medlineplus.gov/thyroiddiseases.html; Office of Women’s Health, Thyroid Disease, https://www.womenshealth.gov/a-z-topics/thyroid-disease; ThedaCare, January Is National Thyroid Awareness Month, https://www.thedacare.org/News-and-Events/Symptoms-and-Conditions/january-is-national-thyroid-awareness-month.aspx
Graphics: Can Stock Photo
