Goiters: what causes an enlarged thyroid gland?

last updated: Mar 28, 2022

6 min read

A goiter is when the thyroid gland is enlarged. The thyroid gland is located near the base of the neck, so goiters often make the front of the neck look swollen. Goiters might sound scary, but they are surprisingly common. Multiple conditions can cause the thyroid to enlarge.


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What is a goiter?

Goiter is an umbrella term that describes an enlarged thyroid gland, which can happen due to various medical conditions. Goiters are usually soft and painless and are located on the front of the neck. Fortunately, they often grow slowly, don’t typically pose an immediate health threat, and are often managed with a watch-and-wait approach.

If you develop a goiter, it doesn’t necessarily mean that you have a serious underlying condition. Still, it is worth having your goiter checked out by a healthcare professional.

Types of goiters

There are multiple types of goiters, including:

  • Diffuse goiter: A diffuse goiter is also called a simple goiter. In this case, the entire thyroid gland swells, creating a large, soft, smooth mass on the front or side of the neck (Can, 2021). 

  • Nodular goiter: Nodular goiters consist of one or more small bumps (nodules) on the thyroid gland. Most thyroid nodules are benign (Durante, 2018). Sometimes nodules group together to form a mass that feels different to the touch (firm and bumpy) than a diffuse goiter. These are called multinodular goiters––the most common thyroid gland disorder (Medeiros-Neto, 2016). 

  • Toxic goiter: This type of goiter may be nodular, multinodular, or diffuse. A toxic goiter makes thyroid hormones, so the body ends up with too much thyroid hormone, creating a health condition known as hyperthyroidism. 

  • Nontoxic goiter: Nontoxic goiters don’t produce any thyroid hormone or affect how the thyroid functions. 

  • Endemic goiter: Endemic goiter, or colloid goiter, is when all thyroid cells grow because of iodine deficiency. This is common in many parts of the world but is rare in the United States.

What causes a goiter?

The thyroid is a butterfly-shaped gland in the neck that sits in front of your windpipe (trachea). Many health and environmental factors can cause your thyroid gland to enlarge.

The thyroid’s main function is using iodine to create hormones. Thyroid hormones are real all-stars in the endocrine system. They affect practically every cell in the body, helping with metabolism, growth, fertility, digestion, heat regulation, and more (Armstrong, 2022). 

If something disrupts this delicate production of hormones, it can affect the thyroid gland and cause a goiter. Causes of goiters include an iodine deficiency, thyroid conditions, hereditary factors, or a side effect of medication. Many of these are benign or easy to resolve, while others require close medical monitoring and intervention.

Hashimoto’s disease

Hashimoto’s disease, or lymphocytic thyroiditis, is an autoimmune disease in which the immune system attacks the thyroid gland and makes it underactive. This causes it to produce lower levels of thyroid hormone (hypothyroidism). 

When the thyroid is damaged and doesn’t produce enough hormones, other glands in the endocrine system try to prompt it to make more. This causes the thyroid to grow and eventually form a goiter (Alkabban, 2021; Patil, 2022).

Hashimoto’s is a common cause of goiters in industrialized countries like the United States. While it can be dangerous if left untreated, it may be diagnosed with a blood test and is treatable with thyroid hormone supplements (levothyroxine) (Patil, 2022).

Graves’ disease

People with Graves’ disease have the opposite problem of those with Hashimoto’s. Graves’ disease is an autoimmune disease that causes a hyperactive thyroid, meaning it produces too many thyroid hormones (hyperthyroidism).

An overstimulated thyroid will start to enlarge, forming a goiter. A Graves’ disease goiter is considered a toxic goiter because of the extra thyroid hormones circulating (Pokhrel, 2021). 

Iodine deficiency

The most common cause of goiter in many parts of the world is low iodine. Our bodies can’t naturally produce it, so we get most of the iodine we need through foods including saltwater fish like cod and canned tuna, green vegetables like spinach, and seaweed (Kapil, 2007). 

When the body doesn’t get enough iodine, the thyroid grows to try and grab as much as it can. The result is a diffuse nontoxic goiter. In countries like the United States, where iodine is added to table salt (“iodized salt”), iodine deficiencies are rare. In other parts of the world, iodine deficiencies are a widespread problem, especially in rainy or mountainous areas where iodine gets washed out of the soil (Alkabban, 2021).


Thyroid tumors can occur with multinodular goiters. Thyroid nodules are usually benign, but they may be cancerous up to 17% of the time.

The relationship between thyroid cancer and goiters is not well understood. Cancer is sometimes incidentally found in nodules after they’ve been removed for a completely different reason. 

Some researchers believe that even when a multinodular goiter is cancerous, it may not pose much of a risk, though more evidence is needed to clarify this (Can, 2021).


Certain medications may trigger thyroid changes and can lead to a goiter. For example, lithium, a drug used for mental health conditions like bipolar disorder, may cause hypothyroidism as a side effect (Patil, 2022).

Amiodarone, an iodine-containing heart medication, may cause hypothyroidism or hyperthyroidism, both of which can cause a goiter to develop (Narayana, 2011).

Hereditary factors

Some people are more likely to experience an enlarged thyroid gland due to genetics. Having a family history of thyroid issues may make you more susceptible to them. This is sometimes the case in areas with ongoing iodine deficiencies; even when iodine supplements are introduced, goiters continue to occur (Can, 2021). 

Goiter symptoms

Goiters aren’t usually diagnosed until a person notices they have a lump in their neck or it’s identified during an examination. Other symptoms and signs of a goiter include (Can, 2021; Medeiros-Neto, 2016):

  • Difficulty swallowing

  • Cough

  • Hoarseness

  • Difficulty breathing

  • Feeling like there’s something in your throat

Sometimes you can prevent a goiter if you catch the cause in advance (like Graves’ disease), but a goiter is often one of the first signs of a thyroid issue.

Goiter diagnosis

If you suspect you have a goiter, no need to panic. Once it’s diagnosed through just a few steps, you can usually then move on to treatment (Durante, 2018; Medeiros-Neto, 2016):

  • Physical examination: Your healthcare provider will gently palpate or touch your neck to feel for swellings or nodules. They’ll ask you to swallow while searching for any swelling or unevenness (asymmetry). 

  • Blood test: A blood test may help identify whether a goiter is associated with hyperthyroidism or hypothyroidism. 

  • Ultrasound: An ultrasound or sonogram is an imaging test that’s especially helpful for diagnosing multinodular goiters, determining their size, and figuring out how widespread they are. An ultrasound may also indicate if it’s appropriate to take a biopsy of the nodules or if it’s safe to take a watch-and-wait approach.

How to get rid of a goiter

Having a goiter may make you feel self-conscious or uncomfortable, but the good news is—most of the time—it’s not an immediate health risk. 

Your healthcare provider may recommend monitoring your goiter while treating the underlying cause. Sometimes, a nontoxic goiter will spontaneously shrink on its own (Can, 2021). 

Goiters may be hard to conceal since they’re in such a prominent position, but many people comfortably live long-term with goiters that don’t need to be removed. 

However, if you feel that your goiter is causing physical problems or decreasing your self-esteem and quality of life, there are a few options for dealing with it, depending on the cause of the goiter.


Drugs won’t necessarily eliminate a goiter entirely, but they can reduce them significantly. 

Nontoxic goiters caused by an iodine deficiency are effectively treated with iodine supplements, which reduce goiter size and how often they occur (Alkabban, 2021).

In the past, a medication called levothyroxine (the same one used to help treat hypothyroidism) was widely used to treat nontoxic goiters. It’s no longer routinely recommended since it doesn’t consistently shrink goiters (Can, 2021). 


Radiation treatment (radioactive iodine, or RAI) is an option for managing toxic goiters. RAI is highly efficient at treating both Graves’ disease and the goiters caused by it. After RAI, there’s a risk of having long-term hypothyroidism, but it’s still a beneficial treatment for many (Mathew, 2021).  

Because it’s less invasive than surgery, RAI treatment is often a good option for older adults with underlying health conditions who need to have their thyroid removed but prefer not to undergo surgery.  


Surgery is another option for treating goiters. In some cases, it’s necessary, such as a goiter that’s obstructing your breathing or swallowing or is causing severe health issues. 

Surgery can also be a good option for large goiters that negatively impact a person’s daily life. It may also be recommended for people who are pregnant (or planning to become pregnant) and can’t safely take radioactive iodine (Bartsch, 2018). 

The surgery involved is called a thyroidectomy and involves removing part or all of the thyroid gland. It’s highly effective at getting rid of goiters since the enlarged thyroid itself is causing the swelling. After surgery, you may need to take daily thyroid hormone supplements to prevent hypothyroidism (Can, 2021). 

Learning that you have a goiter may seem concerning, but fortunately, goiters are common and treatable. If identified and addressed early on, you can effectively manage what’s causing your goiter and identify options for reducing it.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

March 28, 2022

Written by

Nancy LaChance, BSN, RN

Fact checked by

Steve Silvestro, MD

About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.