We all have a thyroid, but do you actually know what yours does? No embarrassment if not — the thyroid is a pretty inconspicuous gland. It’s located at the bottom of your neck and shaped like a butterfly — its main job is to control your body’s metabolic rate, aka how much energy it uses.
You might not notice your thyroid much because when it’s working properly, there’s not much to notice about it. But what happens when it doesn’t function the way it’s supposed to?
Thyroid disorders like hyperthyroidism and hypothyroidism are common, especially in women: Research has estimated that as many as one in eight women will develop thyroid disease in her life.
But a lot of people don’t know they have a thyroid disorder. That’s because the symptoms may be subtle or mistaken for symptoms of another condition — or even a different thyroid disorder.
What are the similarities between hyperthyroidism and hypothyroidism?
Dr. Mayumi Endo, an endocrinologist and director of the Thyroid Nodule Clinic at UW Medical Center – Roosevelt, likes to describe thyroid hormone as the hormone your body secretes if you’re running away from a lion. It’s essential for survival, but too much or too little of it can cause problems.
“Usually you think the symptoms from hyperthyroidism and hypothyroidism are very different, but there are subtle overlaps of symptoms,” Endo says.
Both disorders are more common in people assigned female at birth, people who are pregnant or recently had a baby, and people who have an autoimmune disease like type 1 diabetes, lupus or rheumatoid arthritis.
“Both hyperthyroidism and hypothyroidism can also exacerbate underlying mental health conditions, sometimes in an extreme manner,” Endo explains, sharing the story of one of her patients who had hyperthyroidism and went from only watching comedies to watching horror shows daily because they matched her level of anxiety.
What are the differences between hyperthyroidism and hypothyroidism?
In other ways, though, hyper- and hypothyroidism are nothing alike. The other main hyperthyroidism symptoms involve speeding up of body processes, such as anxiety and irritability, sweating, shaking, heart palpitations, high blood pressure, going to the bathroom more and heat intolerance.
In hypothyroidism, symptoms that indicate slowing of body processes are more common, such as depression, dry skin, irregular periods, joint pain and muscle cramps, a slow heart rate, hoarseness, constipation and cold intolerance.
Is thyroid disease ever a medical emergency?
Symptoms of either disorder may start off subtle but gradually get worse without treatment. Rarely, hyperthyroidism and hypothyroidism can become emergencies if left untreated.
Hyperthyroidism has the potential to be more severe and in rare cases can escalate into a condition known as thyroid storm, a medical emergency where someone’s body pumps out so much thyroid hormone it causes heart and other organ failure.
“Usually thyroid storm is caused by untreated hyperthyroidism. It is most common in patients with newly diagnosed hyperthyroidism who aren’t taking medication consistently,” Endo says.
Rarely, people with hypothyroidism can develop a condition called a myxedema crisis, which is a medical emergency. It manifests as someone feeling lethargic, being confused or unresponsive, being extremely cold, having swelling in the body, and having a hard time breathing.
What causes thyroid disorders?
Hormonal changes during and after menopause are a leading cause of thyroid disease, but there is a long list of other things that can lead to it, too:
- Genetics and genetic mutations
- Graves’ disease (hyperthyroidism)
- Thyroid gland nodules (noncancerous)
- Thyroid cancer
- Hashimoto’s thyroiditis (hypothyroidism)
- Iodine deficiency or overexposure to iodine
- Taking lithium medication
Why is it important to see a doctor about possible thyroid issues?
Aside from the fact that both hyperthyroidism and hypothyroidism can be serious and lead to complications, another reason to see a doctor is to get a correct diagnosis. Both diseases can easily be mistaken for different medical conditions.
“The challenge with these conditions is their symptoms may overlap with lots of different diseases. Both of these diseases can manifest as fatigue, but there are so many other things that cause fatigue,” Endo says.
Diagnosing thyroid disease is relatively easy and typically involves a simple blood test.
Both conditions can be treated, though the methods vary. Hypothyroidism is typically managed with medication to replace low thyroid hormone levels. Hyperthyroidism can be a little trickier to treat in some people. Medication to suppress thyroid hormone production can help, though some people need additional treatment.
In people who don’t respond to medication, there are two options: surgery to remove the thyroid entirely or radioactive iodine treatment to kill off thyroid tissue. This sounds a little scary, but the radioactivity typically gets absorbed solely by the thyroid. And the treatment is a better option than no treatment.
As often as Endo treats people who have thyroid disease, she also regularly sees people who think they have thyroid disease but blood tests show they don’t.
“Often I get a question if fatigue is from thyroid dysfunction, but if the thyroid is normal I encourage patients to look for other causes. If you preoccupy yourself with potential thyroid disease that doesn’t exist, you might be missing something critical,” Endo says.