29: Hypothyroidism — an A to Z Summary and Important Things to Know with Dr. Victor J. Bernet from the Mayo Clinic

In this episode Dr. Bernet describes that Hashimoto's thyroiditis is an autoimmune condition that usually progresses slowly and often leads to low thyroid hormone levels — a condition called hypothyroidism. The best therapy for Hashimoto's thyroiditis is to normalize thyroid hormone levels with medication. A balanced diet and other healthy lifestyle choices may help when you have Hashimoto's, but a specific diet alone is unlikely to reverse the changes caused by the disease.

Hashimoto's thyroiditis develops when your body's immune system mistakenly attacks your thyroid. It's not clear why this happens. Some research seems to indicate that a virus or bacterium might trigger the immune response. It's possible that a genetic predisposition also may be involved in the development of this autoimmune disorder.

A chronic condition that develops over time, Hashimoto's thyroiditis damages the thyroid and eventually can cause hypothyroidism. That means your thyroid no longer produces enough of the hormones it usually makes. If that happens, it can lead to symptoms such as fatigue, sluggishness, constipation, unexplained weight gain, increased sensitivity to cold, joint pain or stiffness, and muscle weakness.

If you have symptoms of hypothyroidism, the most effective way to control them is to take a hormone replacement. That typically involves daily use of a synthetic thyroid hormone called levothyroxine that you take as an oral medication. It is identical to thyroxine, the natural version of a hormone made by your thyroid gland. The medication restores your hormone levels to normal and eliminates hypothyroidism symptoms.

You may hear about products that contain a form of thyroid hormones derived from animals. They often are marketed as being natural. Because they are from animals, however, they aren't natural to the human body, and they potentially can cause health problems. The American Thyroid Association's hypothyroidism guidelines recommend against using these products as a first-line treatment for hypothyroidism.

Although hormone replacement therapy is effective at controlling symptoms of Hashimoto's thyroiditis, it is not a cure. You need to keep taking the medication to keep symptoms at bay. Treatment is usually lifelong. To make sure you get the right amount of hormone replacement for your body, you must have your hormone levels checked with a blood test once or twice a year.

If symptoms linger despite hormone replacement therapy, you may need to have the dose of medication you take each day adjusted. If symptoms persist despite evidence of adequate hormone replacement therapy, it's possible those symptoms could be a result of something other than Hashimoto's thyroiditis. Talk to your health care provider about any bothersome symptoms you have while taking hormone replacement therapy.

Victor J. Bernet, MD, is Chair of the Endocrinology Division at the Mayo Clinic in Jacksonville, Florida and is an Associate Professor in the Mayo Clinic College of Medicine. Dr. Bernet served 21+ years in the Army Medical Corps retiring as a Colonel. He served as Consultant in Endocrinology to the Army Surgeon General, Program Director for the National Capitol Consortium Endocrinology Fellowship and as an Associate Professor of Medicine at the Uniformed Services University of Health Sciences. Dr. Bernet has received numerous military awards, was awarded the "A" Proficiency Designator for professional excellence by the Army Surgeon General and the Peter Forsham Award for Academic Excellence by the Tri-Service Endocrine Society. Dr. Bernet graduated from the Virginia Military Institute and the University of Virginia School of Medicine. Dr. Bernet completed residency at Tripler Army Medical Center and his endocrinology fellowship at Walter Reed Army Medical Center. Dr. Bernet's research interests include: improved diagnostics for thyroid cancer, thyroidectomy related hypocalcemia, thyroid hormone content within supplements as well as management of patient's with thyroid cancer. He is the current Secretary and CEO of the American Thyroid Association.