What Is Thyroid Disease?

Thyroid disease is any condition that affects the functioning of the thyroid gland—a small butterfly-shaped organ in front of the neck that secretes hormones. In the U.S., thyroid disease affects 1 in 10 Americans.

Symptoms of thyroid disease will depend on the exact condition you have. The most common thyroid diseases are hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid). These conditions occur when your body makes too much or too little thyroid hormone, respectively.

Fortunately, there are a variety of treatments you can use if you receive a diagnosis of thyroid disease. Your treatment plan will depend on the type of thyroid disease you have, your symptoms, and your overall health. Generally, the most common treatments include medication and lifestyle changes, and in some cases, surgical procedures.


There are several types of thyroid disease, which include:

  • Hyperthyroidism: An overactive thyroid that occurs as a result of your body producing too much thyroid hormone
  • Hypothyroidism: An underactive thyroid that can happen when your body isn’t able to create enough thyroid hormone
  • Thyroid nodules: Lumps that are either solid or filled with fluid that grow in your thyroid
  • Goiter: An enlarged thyroid 
  • Thyroiditis: Swelling or inflammation of your thyroid gland
  • Thyroid cancer: Growth of cancer cells in your thyroid 


The most common thyroid diseases are hyperthyroidism, hypothyroidism, and thyroid nodules. Symptoms of thyroid disease depend largely on the type of condition that you have. Since thyroid hormones are vital to your body’s metabolism and function, you may also experience symptoms that affect several body parts. 

Generally, hyperthyroidism and hypothyroidism cause very different symptoms. If you receive a diagnosis for either of these conditions, you may experience one or more of the following symptoms:

Symptoms of Hyperthyroidism  Symptoms of Hypothyroidism
Fatigue  Fatigue
Hair loss Hair loss
Difficulty sleeping Difficulty sleeping
Goiter Goiter
Feeling hot Feeling cold
Anxious or racing thoughts Irritability or depressive mood
Difficulty concentrating Slow movement or speech 
Weight loss Weight gain
Increased sweating Cool, pale, and dry skin
Hand tremors or shaking Not being able to sweat or feeling extra tired after working out 
Softened nails Brittle nails 
Skin changes such as patches on your legs  Swollen or puffy pace 
Eye symptoms like blurred vision or swelling Enlargement of the tongue 
Diarrhea  Constipation
Muscle weakness Joint pain 
Elevated heart rate A slowed heart rate 
Shortness of breath Erectile dysfunction or trouble ejaculating in people assigned male at birth 
Light or short menstrual period in people who are assigned female at birth  Heavy and irregular menstrual periods or fertility problems in people who are assigned female at birth 

Symptoms of thyroid nodules look a bit different. If your nodules are small, you might not experience any symptoms at all. However, larger nodules may cause:

  • A noticeable mass or swelling in the neck
  • Neck fullness or discomfort
  • Hoarse voice
  • Difficulty swallowing
  • Difficulty breathing 


Hyperthyroidism and hypothyroidism occur when you produce too much or too little thyroid, respectively. Why a change happens in your hormone levels can depend on a variety of factors, such as:

  • Inflammation of the thyroid
  • Damage to the thyroid gland caused by radiation 
  • Autoimmune conditions such as Hashimoto’s disease or Graves’ disease 
  • Hormonal changes during pregnancy and postpartum 
  • Being born with a congenital thyroid disorder

Risk Factors 

Aside from biological processes that can alter your thyroid hormone levels, a variety of environmental risk factors and lifestyle habits can increase your likelihood of developing symptoms of thyroid disease.

  • Being assigned female at birth
  • Being over the age of 60 years old 
  • Having thyroid surgery 
  • Exposure to radiation or chemotherapy
  • Family history of thyroid disease 
  • Having too much or too little iodine in your body 
  • Smoking cigarettes


If you notice symptoms of thyroid disease or may be at risk of developing the condition, it’s important to see your healthcare provider for proper testing. Getting an accurate thyroid disease diagnosis is critical in order to receive treatment that can help you better manage your condition. 

At your appointment, it’s standard practice for your provider to ask you about your personal and your family’s medical history. They will likely also perform a physical exam and check your neck for any signs of inflammation, tenderness, or apparent nodules and lumps. In some cases, your provider may also choose to take a look at your facial features, hair, and skin for any hyperthyroidism or hypothyroidism symptoms.

If your provider thinks you may be at risk for thyroid disease or notices symptoms of a thyroid condition, they can also order additional testing. These testing methods may include:

  • Thyroid function tests that check your levels of various thyroid hormones including thyroid stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3)
  • Additional blood tests that check for thyroid-related antibodies that your body may be producing to fight harmful cells in your thyroid gland 
  • Imaging tests such as an ultrasound, thyroid nuclear scan, radioactive iodine uptake test, computed tomography (CT) scan, and magnetic resonance imaging (MRI) 
  • Thyroid biopsy (only if you have nodules or lumps) which takes a fluid or tissue sample of the nodules in your thyroid gland


If you receive a diagnosis for thyroid disease, your healthcare provider can help you find a treatment plan that works best for your condition and lifestyle. The goal of treatment is to prevent complications of thyroid disease and to reduce the severity of your symptoms. 

Treatment options vary from person to person and are based on your exact condition. Treatments for hyperthyroidism try to reduce the production of thyroid hormone. Your options for treatment may include:

  • Antithyroid medication such as Tapazole (methimazole) or PTU (propylthiouracil)
  • Radioactive iodine ablation
  • Surgical removal of a part of the thyroid gland 

Treatments of hypothyroidism focus on increasing your production of thyroid hormone. Such treatments may include:

If you have thyroid nodules, your treatment will depend on the size of the lumps and whether cancer cells are present. Based on your condition, your provider may recommend one of the following treatments:

  • Radioactive iodine to shrink the nodules
  • Surgical removal of the nodules 
  • Thyroidectomy to remove the entirety of the thyroid gland
  • Cancer treatment such as radiation or chemotherapy if cancer cells are present 


While there’s no surefire way to prevent thyroid disease, getting screened for thyroid disease if you’re at an increased risk of a condition and seeking early treatment can prevent serious disease complications, like coma or heart failure.

You may also consider trying one or more of the following recommendations to reduce your risk of developing symptoms or to prevent your condition from worsening if you have already received a diagnosis for a type of thyroid disease or thyroid cancer:

  • Quitting smoking
  • Eating anti-inflammatory foods and maintaining a healthy weight that is right for your body 
  • Getting an appropriate amount of iodine in your diet 

Related Conditions

Symptoms of thyroid disease can mimic symptoms of other conditions. During your diagnostic process, your provider may also screen you for related conditions, such as:

Living with Thyroid Disease

While living with the symptoms of thyroid disease can be frustrating, the good news is that thyroid diseases are very treatable with the right treatment plan. That’s why early diagnosis is so important. If you receive a diagnosis for thyroid disease, it’s important to keep in touch with your primary healthcare provider or endocrinologist (a doctor who specializes in hormones). 

Your providers can help you take the necessary steps that can reduce your symptoms and improve your overall condition, such as finding the medications that are right for you and recommending lifestyle changes. 

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16 Sources
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