Young woman feeling her neck while wondering what a heterogeneous thyroid means

Heterogeneous Thyroid: Causes & Treatment

Medically reviewed on Sept 20, 2023 by Jillian Foglesong Stabile, MD, FAAFP. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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The thyroid gland is an organ that regulates your metabolism, governing how much energy you use and how quickly you use it. [1,2] While heterogeneous thyroid isn’t a clinical term, it may be used to describe how the thyroid acts when examined with imaging tools like ultrasounds. [3]

Healthcare providers often rely on ultrasounds to screen for thyroid disorders, which affect some 20 million people in the US. [1,33] An ultrasound emits vibrations that echo off the thyroid, letting technicians observe any abnormalities that may have developed there. [3]

“Heterogeneous echogenicity” may indicate that a small growth known as a thyroid nodule has developed on the thyroid. [3] More commonly, it describes the likely presence of a diffuse thyroid disease (DTD), the most common of which are Hashimoto’s thyroiditis (HT) and Graves’ disease. [3]

If you’ve been diagnosed with a DTD or are concerned you have one, it’s important to understand the distinctions between the two. Below, we’ll explore how the conditions impact thyroid health differently, as well as the treatment modalities available for recovery.

Understanding Hashimoto Thyroiditis (“Hashimoto’s Disease”)

Hashimoto’s disease is a chronic autoimmune disorder that primarily involves the thyroid gland. [4] If you’re diagnosed with it, it means your immune system treats the thyroid as a threat and tries to destroy its cells and surrounding tissues. [4] It is one of the most common causes of hypothyroidism.

If the immune system has caused sufficient damage to the thyroid, this can result in hypothyroidism. [4] Hypothyroidism is a syndrome that can arise in several thyroid conditions. It means your thyroid can no longer produce thyroid hormones on its own. [4]

An underactive thyroid can result in a variety of symptoms, including [4]:

  • Fatigue
  • Sleepiness
  • A feeling of listlessness
  • Muscle weakness or soreness
  • Joint pain
  • Sensitivity to cold temperatures
  • Low mood
  • Difficulty concentrating or remembering things
  • Skin dryness

This type of thyroid dysfunction predominantly affects people assigned female at birth (AFAB) who are middle-aged.4 While its cause isn’t well understood, some evidence suggests the following factors may play a role [4]:

  • Your genes – You may be more likely to develop Hashimoto’s if a family member has been diagnosed with it. It’s thought that Hashimoto's may have a genetic component.
  • Other autoimmune conditions – Your risk of developing Hashimoto’s disease may increase if you have another autoimmune condition, like type 1 diabetes or celiac disease.
  • Environmental factors – Previously contracting an infection and stress have both been linked to the etiology of Hashimoto’s disease. Radiation exposure is also thought to contribute.

It’s unclear how many people have Hashimoto’s disease. However, it’s estimated to be the forerunning cause of hypothyroidism—and hypothyroidism is known to impact about 5 in 100 Americans. [5]

Hashimoto’s Disease Treatment

Treatment of Hashimoto’s disease depends on how severe your symptoms are.4 Some people who develop Hashimoto’s disease may not need medication.4 Rather, lifestyle adjustments may help alleviate mild symptoms, like muscle weakness or low mood.

However, treatment for severe cases of Hashimoto’s disease requires the delivery of an artificial form of the hormones your thyroid can’t make on its own. [4] This is known as hormone replacement therapy. [4]

To determine which hormones you need to replace, your healthcare provider will run tests that evaluate your thyroid hormone levels. [4] Several hormones may be prescribed according to their assessment [4]:

  • T-4 hormone – If you have too little of the hormone T-4, your healthcare provider will likely prescribe levothyroxine. This is a synthetic hormone that mimics the effects of T-4. To counteract the effects of hypothyroidism, you’ll need to take levothyroxine regularly and permanently.
  • T-3 hormone – A normally functioning thyroid supplies your body with T-3 hormone, which it derives from T-4. However, in some Hashimoto’s cases, synthetic T-4 (levothyroxine) isn’t converted into T-3. If this happens to you, a healthcare provider may prescribe you Cytomel® which is a synthetic version of T-3.

Because Cytomel® can have some undesirable side effects (e.g. anxiety, insomnia), your healthcare provider may want to monitor your response initially. This trial period will typically last for at least 3 months, during which you can decide alongside your healthcare provider whether Cytomel® is right for you.

Everlywell Thyroid Health Support Virtual Care

Understanding Graves’ Disease

Graves’ disease is another autoimmune condition that impacts the thyroid. Rather than attacking the thyroid, the immune system causes the thyroid to produce too many thyroid hormones. [6]

As a result, people with Graves’ disease develop hyperthyroidism which causes the metabolism to accelerate. [6] Hyperthyroidism can present with symptoms such as [7]:

  • Trouble sleeping
  • Heart palpitations or rapid heart rate
  • Weight loss
  • Frequent bowel movements
  • Diarrhea
  • Changes in eyesight
  • Eyes that appear large or “bulged”
  • Swelling of the neck (the area surrounding the thyroid)

Most people who develop Graves’ disease are those assigned female at birth (AFAB) who are between 30 and 50 years old.6 Additionally, you may be more likely to develop Graves’ disease if you have another autoimmune condition, such as [6]:

  • Type 1 diabetes
  • Celiac disease
  • Rheumatoid arthritis
  • Vitiligo
  • Lupus

Hyperthyroidism is fairly rare—only about 1.2% of Americans have it.6 However, Graves’ disease is the most common cause of it, responsible for up to 80% of cases in the US. [6]

Graves’ Disease Treatment

When treating Graves’ disease, healthcare providers’ first concern is to protect the heart.6 Hyperthyroidism can be extremely taxing to cardiovascular health. [6]

Fortunately, a rapid heart rate can be effectively treated with beta-blockers.6 These help slow your heart rate down and ensure it stays steady. Most people can stop taking beta-blockers after a period of using medication targeting the thyroid. [6] This is why it is important to know the signs your thyroid medication is working.

Other therapies for a Graves’ disease patient include [6]:

  • Antithyroid medication – Antithyroid medicine works to temper a hyperactive thyroid, slowing the production of thyroid hormones.
  • Radioiodine therapy – Radioiodine therapy prevents the excessive production of hormones by dismantling your thyroid cells. Patients take a radioactive iodine pill or solution over a few months until the thyroid has been destroyed. This may result in hypothyroidism, which can mean you’ll need to take thyroid replacement medication to ensure you get the hormones you need.

Graves disease may also be treated with a thyroidectomy, the surgical removal of the thyroid gland. [6] Like radioiodine therapy, you may need to take thyroid medication to make up for your thyroid’s removal.6 However, beware of signs that thyroid medication is too low so you can have the most successful treatment plan.

How Prevalent Are Thyroid Disorders?

The American Thyroid Association estimates that more than 12% of Americans will develop a thyroid disorder at some point in their lives.1 However, it’s estimated that as many as 60% of people who have one have yet to be diagnosed. [1]

People assigned female at birth are most likely to develop both Graves’ disease and Hashimoto’s disease.8 Recent research also suggests people AFAB are at a higher risk of developing thyroid cancer [8]:

  • In 2020, a study from the World Journal of Surgical Oncology demonstrated that people with Graves’ disease are 2.5 more likely to develop thyroid cancer than the rest of the population. [10]
  • A separate 2020 study observed that the inflammatory processes behind Hashimoto’s disease may be a risk factor for thyroid cancer. [10]

As research into the connection between thyroid disorders and cancer develops, diagnostic tools become ever more important in protecting long-term health. Testing for thyroid conditions, in particular, can be a valuable tool for addressing and preempting illness earlier.

How To Know If You Have A Thyroid Condition

If you’re concerned about symptoms that affect both your physical and emotional well-being, it may be worth ruling out a thyroid condition. You can take the following steps to ensure you’re properly diagnosed:

  • Take note of your symptoms – It can be helpful to keep a concrete record of your symptoms that you can share with a healthcare provider later. For example, if you feel sensitive to cold often, try taking and logging your temperature. You might also try self-examining your neck, as a swollen-looking neck may indicate hyperthyroidism.
  • Get a sense of your family’s medical history – Remember, certain thyroid conditions are suspected to have a genetic component. If you can, it may be worth asking family members if they’ve ever been diagnosed with an autoimmune or thyroid condition.
  • Reach out to a healthcare provider – Your healthcare provider is your foremost ally for assessing your systems and prescribing you an appropriate treatment protocol. Since thyroid dysfunction can require permanent treatment, it’s important to communicate with them early to begin evaluation as soon as possible.
  • Undergo testing – Your healthcare provider will order testing if they believe you may be a candidate for a thyroid condition. These thyroid tests may include blood work, ultrasounds, or other imaging tools.

If you want to check up on your thyroid health before seeing a healthcare provider, at-home tests are also available. Many of these can measure thyroid hormones like TSH, T3, and T4 to assess how well your thyroid is functioning.

Keep Up With Your Thyroid Health With Everlywell

From physician-reviewed test kits to connections to licensed telehealth providers, Everlywell offers a variety of health tools and treatment services no matter what health issues you’re up against.

With our easy-to-use At-Home Thyroid Test, you can screen for abnormal thyroid hormone levels with sample collection at home—and get trustworthy, CLIA-certified lab results just days after we receive your sample. If your results indicate you need more care, we’ll connect you to a qualified healthcare provider who can help you get back on track to well-being.

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  1. General Information/Press Room. American Thyroid Association. (n.d.-a). URL. Accessed Sept 15, 2023.
  2. professional, C. C. medical. (n.d.-d). Thyroid disease: Causes, symptoms, risk factors, testing & treatment. Cleveland Clinic. URL. Accessed Sept 15, 2023.
  3. Park, M., Park, S. H., Kim, E.-K., Yoon, J. H., Moon, H. J., Lee, H. S., & Kwak, J. Y. (2013, November 16). Heterogeneous echogenicity of the underlying thyroid parenchyma: How does this affect the analysis of a thyroid nodule? - BMC cancer. BioMed Central. URL. Accessed Sept 15, 2023.
  4. Mayo Foundation for Medical Education and Research. (n.d.-b). Hashimoto’s disease. Mayo Clinic. URL. Accessed Sept 15, 2023.
  5. U.S. Department of Health and Human Services. (n.d.-g). Hashimoto’s disease - NIDDK. National Institute of Diabetes and Digestive and Kidney Diseases. URL. Accessed Sept 15, 2023.
  6. professional, C. C. medical. (n.d.-b). Graves’ disease: What it is, causes, symptoms & treatment. Cleveland Clinic. URL. Accessed Sept 15, 2023.
  7. professional, C. C. medical. (n.d.-c). Hyperthyroidism: Symptoms, causes, treatment & medication. Cleveland Clinic. URL. Accessed Sept 15, 2023.
  8. Mayo Foundation for Medical Education and Research. (2023a, April 26). Thyroid cancer. Mayo Clinic. URL. Accessed Sept 15, 2023.
  9. Kwon, H., & Moon, B.-I. (2020, October 13). Prognosis of papillary thyroid cancer in patients with graves’ disease: A propensity score-matched analysis - World Journal of Surgical Oncology. BioMed Central. URL. Accessed Sept 15, 2023.
  10. U;, F.-R. (n.d.). Hashimoto’s thyroiditis as a risk factor for thyroid cancer. Current opinion in endocrinology, diabetes, and obesity. URL. Accessed Sept 15, 2023.
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