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The Ultimate Guide to Hyperthyroidism Lab Testing

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The Ultimate Guide to Hyperthyroidism Lab Testing

Hyperthyroidism, also known as overactive thyroid, is a condition affecting 1 in 100 Americans. More common in women than men, this condition affects the entire body as all bodily systems use thyroid hormones.

This article will discuss what hyperthyroidism is, including its symptoms and causes. We’ll also discuss how to test for hyperthyroidism and conventional and alternative medicine treatments to cover a thorough integrative approach.


What is Hyperthyroidism?

The overproduction of thyroid hormones characterizes hyperthyroidism. The thyroid gland is a butterfly-shaped gland that sits in your neck. It functions to produce hormones through a feedback loop called the Hypothalamic Pituitary Thyroid (HPT) axis. When the body needs more thyroid hormone, the hypothalamus releases Thyroid-Releasing Hormone (TRH) to the pituitary gland. The pituitary gland will then release Thyroid Stimulating Hormone (TSH) to the thyroid gland. The thyroid gland then releases two hormones: thyroxine (T4) and triiodothyronine (T3).

Every system in the body utilizes these hormones. Most of the hormones produced are T4; however, T3 is more metabolically active. Thus, T4 gets converted into T3 in the peripheral tissues, especially the liver and kidney. The hypothalamus can sense the amount of circulating T4 and T3. In a healthy functioning thyroid gland, when more of these hormones are needed, more TRH and TSH get released. Conversely, too much T4 and T3 in the blood will suppress TRH and TSH, consequently decreasing the production of T4 and T3.

In hyperthyroidism, the thyroid gland does not obey this feedback mechanism and, despite low TSH signaling, will still make large amounts of thyroid hormones.

Hyperthyroidism Symptoms

Because every body system uses thyroid hormones, the symptoms are numerous and vast:

  • Irregular and fast heartbeat
  • Heart palpitations
  • Excessive sweating
  • Irritability, anxiety, and nervousness
  • Sleeplessness
  • Excessive weight loss
  • Increased hunger
  • Fatigue
  • Muscle weakness
  • Goiter (enlargement of the thyroid gland)
  • Thinning skin
  • Brittle hair and nails
  • Menstrual irregularities
  • Infertility
  • Frequent bowel movements

Due to these symptoms, complications of hyperthyroidism can affect the heart, bones, eyes, and skin.

Cardiac complications

Hyperthyroidism can lead to atrial fibrillation, a heart rhythm disorder. This will place the person at an increased risk for a stroke. Additionally, congestive heart failure, a condition where the heart slows and thus does not pump enough blood and oxygen through the body, is also of concern.

Skeletal complications

Hyperthyroidism leads to difficulty transporting calcium into the bones, increasing the risk of osteoporosis.

Vision complications

Thyroid eye disease, as it's referred to, occurs when the muscles and tissues surrounding the eye receive too many thyroid hormones. More common in smokers, this can cause bulging of the eyes, red eyes, and retracted or inflamed eyelids. The person may have double vision, light sensitivity, and painful pressure in the eye.

Skin complications

Dermopathy usually occurs on the shins and feet and is characterized by a color change and swelling.

Additionally, hyperthyroidism raises the risk of a thyrotoxic crisis, also called a thyroid storm. This life-threatening condition requires immediate medical care, characterized by rapid heartbeat, confusion and delirium, nausea, vomiting, fever, and dehydration.

What Causes Hyperthyroidism?

Hyperthyroidism can be caused by the following: Graves' disease, thyroiditis, thyroid nodules, excessive iodine consumption, overmedication, and a pituitary tumor.

Graves' Disease

Graves' disease is an autoimmune disorder that causes the thyroid gland to overproduce thyroid hormones. This is the most common cause of hyperthyroidism.


Thyroiditis is an inflammatory condition of the thyroid gland. The inflammation can cause the gland to swell and leak out thyroid hormones. It's important to note that thyroiditis can initially cause hyperthyroidism, and over time it can lead to low thyroid hormone output, called hypothyroidism.

Thyroid Nodules

Nodules are lumps in the thyroid gland that can become overactive and increase thyroid hormone output. Nodules are most common in older people.


Iodine is an essential nutrient for the thyroid gland as it aids in creating thyroid hormones. However, too much iodine can cause those hormones to cease production. High levels of iodine can be found in certain supplements, over-the-counter medications such as cough syrups, and certain heart medications.


Anyone diagnosed with hypothyroidism will be on a daily dose of thyroid medication for life. Overmedication can happen if an extra dosage is taken or if thyroid hormone levels are not properly monitored. Additionally, other medications can interact with thyroid medications and inhibit their breakdown, thus causing hormone levels to be high.

Pituitary tumor

A noncancerous pituitary tumor may also cause the overproduction of thyroid hormones.

Ultimate Guide to Hyperthyroidism Lab Testing

A full thyroid panel to assess hyperthyroidism should include TSH, T4, T3, free T4, free T3, and thyroid antibodies, including thyroid-stimulating immunoglobulin (TSI). Since most T4 and T3 are bound in the bloodstream, it's important to see the free levels of these hormones, as they are metabolically active. Additionally, thyroid antibodies will tell us if an autoimmune process is occurring.

GI-MAP is a comprehensive stool test showing the presence of numerous microbes that make up the microbiome. This test has a section showing certain microbes that have been linked to autoimmune conditions, such as Graves' disease. The bacteria Lactobacillus and Bifidobacteria are two of the most beneficial bacteria found within the microbiome and have been found in lower levels in Graves' disease. Additionally, the bacteria Helicobacter pylori (H. pylori) seems to play a role in developing autoimmune thyroid conditions, specifically. The GI-MAP tests for H. pylori and its virulence factors, which tell more about the infection and help to eliminate it. Lastly, the microbiome influences concentrations of nutrients in the body, including one of the most crucial thyroid nutrients, iodine.  

Micronutrients, such as iodine, selenium, and vitamin d, are important nutrients for thyroid functioning, and hyperthyroidism can deplete levels of certain micronutrients, such as carnitine. A micronutrient test will assess levels of many different micronutrient tests to identify deficiencies and surpluses.

Other Lab Test to Check

Radioactive thyroid scan: This scan requires oral injection of radioactive iodine. Blood flow to the thyroid will then be monitored via scan. High amounts of blood flow are indicative of Graves' disease.

Hormone panel: Since hyperthyroidism can cause menstrual irregularities, checking hormones can help to identify the resulting hormonal imbalances. For men, hyperthyroidism may negatively impact sperm and hormone levels, and thus a hormone panel may be warranted.

Conventional Medicine Treatment for Hyperthyroidism

Due to the severity and seriousness of hyperthyroidism, conventional medical treatments are first-line therapies and include medications, radioiodine therapy, and surgery.


There are two major types of medications for hyperthyroidism: those that slow the thyroid and cardiac drugs. Medications that slow thyroid hormone production include Methimazole and Propylthiouracil. Beta-blockers are a fast-acting type of cardiovascular drug that aims to slow down the heart rate. The effects can be quick; however, they do not affect thyroid hormone output.

Radioiodine Therapy

Radioactive therapy is radioactive iodine given in pill form. Radioactive iodine will destroy the cells of the thyroid gland. Most people who opt for this treatment will eventually develop hypothyroidism due to the destruction of the thyroid gland and, therefore, a lack of thyroid hormone production.  


Surgery may be indicated if the patient has a large goiter or is pregnant and cannot take medication. Like radioiodine therapy, hypothyroidism is a common development post-surgery.


Since overconsumption of iodine may lead to hyperthyroidism, limiting the amount of iodine-containing foods may be helpful. High iodine-containing foods include seaweed, kelp, fish, and iodine-fortified foods such as iodized salts and bread products.

Supplements for Hyperthyroidism

Selenium is required for proper thyroid hormone synthesis. It can be helpful in hypothyroidism but also in hyperthyroidism. There is an increased risk of Graves' disease with low selenium intake, and selenium supplementation in those with Graves' disease had faster remission rates of hyperthyroidism. Lastly, selenium supplementation seemed to specifically help with the ophthalmological symptoms of Graves' disease.

L-carnitine can be effective in the treatment of hyperthyroidism. A randomized placebo control trial of 50 women over six months showed supplementation of l-carnitine reversed hyperthyroid symptoms and increased bone mineral density. The doses used varied from two to four grams per day.

As discussed above, the microbiome can play an important role in hyperthyroidism. Bacteria in the microbiome seem to regulate immune cell development, an essential factor in autoimmune conditions such as Graves' disease. A probiotic including Lactobacillus and Bifidobacteria may be beneficial, as those bacteria are beneficial for the microbiome and are present in lower levels in those with Graves' disease.  


Hyperthyroidism is a condition with a wide array of symptoms affecting all body systems. Testing can aid in the diagnosis of hyperthyroidism, as well as help to identify underlying causative factors. A treatment plan including both conventional and functional medicine may aid in symptom relief and, thus, improve the quality of life for those with hyperthyroidism.

The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.
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