The Thyroid

The thyroid gland is the “master controller” of metabolism.

About Goiters and Nodules

A shortage of iodine in the diet is the world’s number one cause of an enlarged thyroid (commonly known as “goiter”).1 In fact, an estimated 0.7 billion people worldwide are affected by an iodine deficiency.2

How to recognize a goiter

A goiter forms when the thyroid gland attempts to compensate for iodine deficiency and the associated low and/or failed production of thyroid hormones. In this process, it gradually grows from its normal size.1

A person with an immensely enlarged thyroid may have problems swallowing and breathing.3

The American Association of Clinical Endocrinologists recommends the so-called “neck check” to help people recognize a possibly enlarged thyroid.4

Simple visual classification can be inaccurate — primarily due to the possibility of human error and variations in individual anatomy (e.g. a muscular neck can conceal an enlarged thyroid) — and should by no means serve as a substitute for a specific diagnosis by a doctor.

How to recognize a nodule

Thyroid nodules are abnormal overgrowths of tissue in the thyroid gland.5 Some people develop one nodule while others develop many.5 Thyroid nodules are relatively common, with as many as half of all people having at least one nodule by the time they reach the age of 60.5 Just as with goiter formation, the formation of thyroid nodules can be caused by insufficient iodine in the diet.6

Thyroid nodules are classified by scans as “hot”, “warm” or “cold”. If a nodule does not produce iodine then it will appear “cold” on the scan. Those that do produce iodine will show up darker and are called “hot”. Approximately 85% of nodules are cold, 10% are warm and 5% are hot. Of these, 85% of cold nodules are benign (non-cancerous), as are 90% and 95% of warm and hot nodules, respectively.7

Initially, most thyroid nodules do not cause any noticeable symptoms.6 They often go undiscovered until the next routine medical examination or on imaging tests such as computed tomography (CT) scans or neck ultrasound, done for unrelated reasons.6 As the thyroid nodules grow further, the following symptoms can occur (although this is rather rare):

  • Difficulty swallowing or pain upon swallowing6
  • Difficulty breathing6
  • Hoarseness6
  • Symptoms of hyperthyroidism5

Upon the onset of breathing difficulties, , a doctor should be consulted immediately. If you believe that a nodule has formed in your own thyroid gland, you can perform the so-called “neck check”, as set forth by the American Association of Clinical Endocrinologists.4

Diagnosis and treatment

Following a simple physical examination by a doctor, a blood sample is taken to determine whether there is a sufficient amount of TSH in the bloodstream.1 This hormone is an indicator of whether the thyroid gland is functioning normally. Ultrasonography (an ultrasound scan) is performed to determine the actual size of the nodules and thyroid gland.1 This scan is completely painless. Other methods for examining nodules include a radioactive iodine scan and fine-needle biopsy.1

How are goiter and nodules treated?

Not every goiter and nodule requires treatment.3 Depending on their type and size, their development might merely be regularly observed. In general, there are three treatments. The choice of therapy depends on each individual patient’s diagnosis. The primary aim of treatment is to shrink the enlarged thyroid gland and the nodules.

Treatment with medication(s)

For goiters and nodules that occur due to an iodine deficiency, iodine supplementation can be given.1 If the goiter is due to Hashimoto’s thyroiditis and you have hypothyroidism, you will be given the appropriate medication to restore your thyroid hormone levels to normal.1 When goiters and nodules are accompanied by hyperthyroidism (e.g. as in the case with “hot” nodules), additional medications are prescribed.1,7

Radioiodine therapy

Radioiodine is administered on a one-off basis, in the form of a pill. It enters the thyroid gland via the bloodstream, where it is stored — and prompts the shrinkage of the thyroid tissue due to short-range radiation.3

Thyroid surgery

If  a thyroid nodule is detected, one treatment involves removing the whole thyroid gland via surgery. In addition, the thyroid gland can be partially or completely removed if a goiter or nodules are causing immense discomfort. Following such a procedure, treatment with substitution therapy is required to replace thyroid hormone production.3

Regardless of the particular therapy — and also to help prevent thyroid disorders — you should always ensure adequate iodine intake in your diet.

  1. American Thyroid Association. Goiter. 2016 Available at Last accessed February 2022
  2. United Nations. Sixth report on the world nutrition situation. Available at Last accessed February 2022
  3. Goiters: abnormally large thyroid glands. Available at Last accessed February 2022
  4. American Association of Clinical Endocrinologists. Neck check. Available at Last accessed February 2022
  5. Thyroid nodules: prevalence, symptoms, causes, diagnosis, and treatments. Available at Last accessed February 2022
  6. American Thyroid Association. Thyroid nodules. Available at Last accessed February 2022
  7. Fine needle biopsy of thyroid nodules. Is it cancer or just a benign nodule? Available at Last accessed February 2022


Date of preparation: February 2022