Your thyroid plays a key role in energy, metabolism, and hormone balance. Learn how it works, what happens when hormone levels shift, and how to recognize signs of thyroid disorders like hypothyroidism and hyperthyroidism.
Thyroid Anatomy
The thyroid gland is an organ shaped like a butterfly that can be found in our necks. More specifically, it's inferior to the larynx–aka the voice box–and anterior to the trachea, which is also colloquially known as the windpipe.
The thyroid's medial region is known as the isthmus; on either side are its left and right lobes, which look like wings. The parathyroid glands are embedded within these lobes, and are mostly found on their posterior surfaces.
For the most part, the thyroid's tissue is made up of thyroid follicles, which are central cavities filled with colloids, or sticky fluids. The colloid is where the thyroid produces its hormones, and is gated by a wall of epithelial follicle cells.
Thyroid Function
Though the thyroid's anatomy seems quite simple, its function is important: it produces a set of hormones that are instrumental in metabolism, protein synthesis, and tissue growth as well as development when we're children.
Thyroid Hormones: T3 and T4
The two thyroid-produced hormones are called T3 and T4. They're frequently called "metabolic hormones" because our basal metabolic rate–or how much energy we use when we're resting–is influenced by how much T3 and T4 we have floating around our bodies. This process hinges upon iodine, a substance that's not only essential but also unique to thyroid hormones.
Role in Growth and Development
We need sufficient levels of thyroid hormones in our bodies to make proteins, as well as to develop and grow tissues from when we're developing fetuses through childhood. In fact, T3 and T4 are especially important in the nervous system's healthy development, and continue to support its function in adulthood.
Impact on Reproductive Health
T3 and T4 have complex relationships with our reproductive hormones, too. Because of this, imbalances in them can affect our fertility, sex drive, and other reproductive behaviors.
Cardiovascular Effects
Excessive levels of thyroid hormones speed up our heart rate and blood pressure, and strengthen the heartbeat. This explains some of the symptoms experienced in hyperthyroidism.
Thyroid Disorders
Thyroid disorders–which generally stem from dysregulated thyroid hormones–may have varied and sometimes even severe effects on the body due to the diverse functions of the T3 and T4 hormones.
Hyperthyroidism
Hyperthyroidism occurs when the thyroid produces too many hormones. Excessive levels of thyroid hormones can speed up heart rate and blood pressure, and strengthen the heartbeat. Graves' disease is the most common origin of hyperthyroidism.
Hypothyroidism
Hypothyroidism results from the thyroid producing too few hormones. When T3 and T4 are downregulated (aka produced too little), you could develop a condition known as hypothyroidism. This could lead to a number of symptoms, such as joint pain. Hashimoto's disease is the most common culprit behind hypothyroidism.
Joint Pain and Muscle Symptoms
According to the Mayo Clinic, hypothyroidism (a condition caused by an underactive thyroid) can lead to joint pain and other similar side effects, including1:
- Muscle tenderness, stiffness, and general aches, often in your hips and shoulders
- Carpal tunnel syndrome
- Joint stiffness
- Swelling of the small joints in your feet and hands
While generic pain medications like acetaminophen (Tylenol) and ibuprofen (Advil) may help ease the pain, the primary treatment doctors will often turn to is the appropriate thyroid replacement therapy, which can often yield dramatic improvement in those suffering from these undesirable symptoms.
The Mayo Clinic suggests that you follow up with your doctor if your current treatment course is not yielding results in joint swelling, pain, and stiffness you're experiencing; this is important because those who have hypothyroidism are often predisposed to developing a host of other autoimmune diseases, including rheumatoid arthritis.
Thyroiditis
Inflammation of the thyroid gland can occur in several forms:
Acute Thyroiditis
According to the Cleveland Clinic, the most probable culprit behind pain in the thyroid is acute thyroiditis, or inflammation of the thyroid gland that occurs over the course of a few days2. Extremely rare, acute thyroiditis is caused by bacteria and leads to intense pain in the thyroid region that's accompanied by a high fever. Your doctor will prescribe you antibiotics, but you may need surgery to remove the part of your thyroid that's infected.
Subacute Thyroiditis
Another type of thyroiditis is known as subacute thyroiditis; it unfolds over a period of a few weeks and is generally caused by a virus. Its symptoms include pain behind the ear and in the jaw as well as a low-grade fever.
Chronic Thyroiditis (Hashimoto's)
A final type of thyroiditis is known as chronic thyroiditis; it's also referred to as Hashimoto's thyroiditis. Its underlying culprit is an autoimmune process that activates the white blood cells, which in turn begin attacking the body's thyroid cells. The thyroid will then produce new cells in an attempt to survive this attack but will eventually fail. Once you reach this point, you'll need to be on thyroid hormone treatments for the rest of their life.
Thyroid Cancer
The thyroid is also susceptible to cancer. Thyroid nodules may be benign or cancerous. Your doctor may follow up thyroid function tests with imaging tests, such as ultrasounds, thyroid scans, or radioactive iodine uptake tests to diagnose thyroid cancer.
Hair Loss Related to Thyroid Disorders
Thyroid disorders could lead to hair loss, among a host of other undesirable symptoms. According to the British Thyroid Foundation, you may experience hair loss as a side effect if you have prolonged and severe hyper- or hypothyroidism3.
Diffuse Hair Loss from Thyroid Dysfunction
In general, this symptom manifests in diffuse hair loss that ultimately covers your entire scalp as opposed to distinct areas of the head. In some ways, perhaps this is a positive attribute, as the hair thins uniformly. And the good news is that individuals' hair tends to regrow if their thyroid disorder is treated successfully, though this usually takes many months and all the lost hair may not grow back. It's also helpful to note that mild or short-lived thyroid disorders don't usually cause hair loss.
Hair Loss from Thyroid Medications
Another instance in which thyroid disorders could lead to hair loss, ironically, is during their treatment. Some anti-thyroid drugs–namely propylthiouracil and carbimazole–may, rarely, lead to diffuse hair loss. Oftentimes, it's quite difficult to pinpoint whether the hair loss is because of the thyroid's overactivity or the drug's side effects. This phenomenon is, however, unusual, and people very rarely seek alternative anti-thyroid treatments.
Secondary Autoimmune Hair Loss
A third way in which thyroid disorders may culminate in hair loss is if one has an autoimmune thyroid disease that leads to the development of a secondary autoimmune condition. Most individuals with hyper- or hypothyroidism have an autoimmune form of thyroid disease, and people with one autoimmune disorder are likely to develop another. Alopecia areata is an autoimmune condition often developed by individuals who also have an autoimmune thyroid disorder; it leads to discrete areas of hair loss.
Diagnosing Thyroid Issues
Physicians will use a collection of assessments called thyroid function tests to see how well your thyroid is functioning, as well as to find the root cause of issues you may be having, such as hypothyroidism or hyperthyroidism.
These tests help your doctor diagnose a host of other thyroid-related issues as well, such as Graves' disease, Hashimoto's disease, thyroid cancer, and thyroid nodules.
Thyroid function tests generally check for levels of T3, T4, as well as various thyroid-specific antibodies circulating in the blood.
Types of Thyroid Function Tests
There are four major types of thyroid function tests:
TSH Test
Physicians often perform this test first. TSH is a hormone made by the pituitary gland (located in the brain). It tells your thyroid how much T3 and T4 it should produce. If you have low TSH, you likely have hyperthyroidism; if you have high TSH, you likely have hypothyroidism.
If your TSH test comes back abnormal, you'll need at least one more thyroid function test to hone in on the root cause of your thyroid issue.
T4 Tests
Low levels of T4 mean you could have hypothyroidism, while high levels of it could mean you have hyperthyroidism.
However, abnormal results could also not be due to thyroid issues, as some severe illnesses or other medications (such as oral contraceptives and asthma medications) could skew your results.
T3 Test
Your physician may order this test if they think you could have hyperthyroidism even if your T4 level is normal. This is because sometimes T4 could be normal while T3 is high.
Thyroid Antibody Tests
These tests could help diagnose assorted autoimmune thyroid disorders, including Hashimoto's disease (the most common culprit behind hypothyroidism) and Graves' disease (the most common origin of hyperthyroidism).
This is because thyroid antibodies are made in inordinately high amounts when your immune system is attacking the thyroid gland by mistake. Oftentimes, your physician may order these tests to follow-up other abnormal thyroid function tests.
Imaging Tests
Your doctor may follow up thyroid function tests with imaging tests, such as ultrasounds, thyroid scans, or radioactive iodine uptake tests.
The Ezra full-body scan could find cancerous or other actionable states in your thyroid.
Managing Thyroid Health
Most thyroid complications require surgery or medication, but some lifestyle changes may help with your thyroid's functioning. Here are a few:
Rethink your morning coffee
If you take medication for hypothyroidism, avoid drinking coffee too soon afterward. Research shows that coffee can interfere with the way your body absorbs the replacement hormones4.
This effect may be due to the caffeine in coffee. You should wait to consume any caffeine-containing beverage, including tea or soda, for at least an hour after taking thyroid medication.
Watch your iodine intake
Excessive levels of iodine can make thyroid issues worse, especially hyperthyroidism. Watch your iodine intake, particularly if you take iodine-containing medications or receive radiology procedures that involve being injected with iodinated dye.
Avoid foods high in iodine, such as kelp, iodized salt, and iodized cheese, milk, eggs, and saltwater fish.
Cook your goitrogens
Some foods contain compounds called goitrogens that may disrupt the production of thyroid hormones by interfering with the use of iodine5. Foods with goitrogens include soy products and cruciferous vegetables like cabbage, cauliflower, and broccoli.
Goitrogens are more effective in raw foods. Steam or cook these foods instead of eating them raw to reduce goitrogenic properties.
Consider going gluten-free
Hashimoto's thyroiditis, also known as Hashimoto's disease, is a common autoimmune condition that causes hypothyroidism. Research suggests that it is more common in individuals with celiac disease, an autoimmune condition triggered by gluten consumption6.
If you're concerned about your thyroid, ask your doctor whether you should eliminate gluten or be tested for celiac disease. One study, published in July 2019 in Experimental and Clinical Endocrinology & Diabetes, suggested that women with autoimmune thyroid disease may benefit from a gluten-free diet7. Avoid drastic dietary changes without consulting your healthcare provider.
Manage your stress
Cortisol, known as the "stress hormone," is produced by the adrenal gland as part of the body's stress response8. Cortisol helps your body prepare for the "fight or flight" response. However, chronically high cortisol levels can be harmful to your health over a long period of time. Researchers have even found that cortisol may affect thyroid function, which may even affect brain health9,10.
Managing and preventing stress may help preserve the health of your thyroid. Learn and practice relaxation techniques, like meditation or yoga. Exercise regularly, avoid fatty and sugary foods, try to keep to a regular sleep schedule, and cut back on caffeine, smoking, and alcohol.
It's important you see a doctor as soon as you notice any pain in your thyroid.
Concerned about your thyroid health? An MRI scan is a fast, painless, effective way to detect and diagnose thyroid tumors and lesions. If you are at risk of thyroid cancer and want a screening, the Ezra full-body MRI scan can help you take control of your health and get the answers you need.
