Feeling Out of Whack? It Could Be Your Thyroid

That small, butterfly-shaped gland in your neck called the thyroid is more important than many people realize.

Think of it as the master conductor of the body’s orchestra, quietly guiding and coordinating the performance of nearly every organ and system. Just as a conductor ensures each section of the orchestra plays in harmony, the thyroid helps regulate essential functions through the hormones it produces. But if the conductor falters, even slightly, the entire symphony can fall apart.

The same is true for the body when the thyroid isn’t functioning properly.

More than 20 million people in the United States are living with thyroid issues, and an estimated 12% of Americans will develop a thyroid condition in their lifetime. Up to 60% of those affected, however, may not even realize they have a thyroid disorder, according to the American Thyroid Foundation.

Laura Kelley, media relations professional in the CU Anschutz Office of Communications, speaks with Bryan Haugen, MD, professor of medicine at the University of Colorado School of Medicine and a leading expert in thyroid research. The two discuss the role of the thyroid, why it matters and how to recognize when something might be off.

What does the thyroid gland do?

It produces thyroid hormones which help regulate metabolism, energy levels, temperature control and the function of organs such as the brain, heart and muscles. These hormones are essential for keeping the body running smoothly.

How do thyroid hormones affect metabolism and energy?

The thyroid makes two main hormones: T4 and T3. T4 is mostly inactive and gets converted into T3, the active form, by enzymes in the body. T3 then acts on cells through thyroid hormone receptors helping regulate how quickly the body uses energy and how well organs function. In short, thyroid hormones keep your body's systems working at the right speed.

What is hypothyroidism, and what causes it?

Hypothyroidism means the body doesn’t produce enough thyroid hormone. In the U.S., the most common causes are Hashimoto’s disease, an autoimmune condition where the immune system attacks the thyroid. The next most common cause of hypothyroidism is surgical removal of the thyroid gland. Around the world iodine deficiency remains a major cause, especially in children, where it can affect growth and brain development. Hashimoto’s symptoms include fatigue, feeling cold, dry skin, constipation, weight gain and brain fog. A simple way to describe it: Your body is running slower than usual.

What is hyperthyroidism, and how is it different?

Hyperthyroidism is the opposite. It means too much thyroid hormone is being made. The most common cause is Graves’ disease, another autoimmune condition where antibodies overstimulate the thyroid. Other causes include overactive thyroid nodules or taking too much thyroid medication. Symptoms can include a racing heartbeat, anxiety, trouble sleeping, sweating, frequent bowel movements, weight loss and sometimes fatigue due to poor sleep. It often feels like the body is in overdrive like having too much caffeine.

How are thyroid disorders diagnosed?

The main test used is the TSH (thyroid-stimulating hormone) test. TSH is made by the pituitary gland in the brain and responds to thyroid hormone levels in the blood. High TSH usually means hypothyroidism, and low TSH points to hyperthyroidism. Other tests, including Free T4, a blood test that measures the amount of unbound or free, thyroxine (T4) in your bloodstream and thyroid antibody levels, can help confirm a diagnosis or uncover autoimmune causes.

Are thyroid conditions more common in women?

Women are significantly more likely than men to develop thyroid disorders. This is mainly because women are more prone to autoimmune diseases. Factors like hormones, especially estrogen, and genetics (women have two X chromosomes, men only one) may contribute.

How do thyroid problems affect mental health and thinking?

Thyroid hormones are essential for brain function. Low or high levels can lead to issues like anxiety, depression, difficulty concentrating and mood swings. Many people don’t realize that what feels like a mental health issue could be thyroid related.

Can thyroid medication affect mood or mental symptoms?

Yes. If someone takes too much or too little thyroid hormone, it can mimic or worsen symptoms like anxiety, depression or even obsessive thinking. That’s why correct dosing and regular monitoring are so important.

How are thyroid levels monitored during treatment?

For hypothyroidism, doctors usually monitor TSH levels and track symptoms to find the right dose of thyroid hormone – most often levothyroxine. For hyperthyroidism, both TSH and Free T4 are typically followed more closely, especially if anti-thyroid medications are being used.

How often should thyroid levels be checked?

When starting or adjusting thyroid medication, levels are usually checked every six to eight weeks. Once the dose is stable and symptoms are well controlled, thyroid levels are generally checked every six to 12 months. People with other health conditions, especially related to mood or heart function, may need more frequent checks.

What about thyroid care during pregnancy?

Thyroid care during pregnancy is particularly important. A developing baby relies on the mother’s thyroid hormone, especially in the first trimester. Managing thyroid function during pregnancy requires special attention and, ideally, care from a provider familiar with treating thyroid disease in expectant mothers.

Anything else patients should know?

Thyroid disorders are common and often go undiagnosed, especially since their symptoms like fatigue, weight changes or anxiety can be mistaken for other conditions. The good news is that with the right diagnosis and treatment, most people with thyroid conditions can feel well and lead healthy lives. If you suspect a thyroid issue, talk to your doctor and ask about testing, especially if you have a family history or unexplained symptoms.