Goiter Meaning
In Biology, we study about the human body, its organs, and functions of the different organs. Now, it is widespread knowledge that all the organs in our system work to keep our body in its best form. The human body also has essential vitamins, proteins, minerals, etc. All these components help the body to function efficiently. Sometimes, our body may face a deficiency in one or more of these components. This deficiency may lead to certain conditions. Goitre disease is due to a lack of iodine, and other reasons. In this article, we will know Goiter’s meaning and how it affects the human body.
What is A Goiter?
The definition of Goiter states that it is an enlargement of the thyroid gland on the front and sides of the neck. It is the result of abnormal thyroid secretion, especially hypothyroidism due to a lack of iodine in the diet.
Let’s discuss thyroid in brief for you to understand the topic better. The thyroid is a butterfly-shaped endocrine gland (secreting hormones directly into the blood) in your neck. It makes and secretes two hormones directly into the blood- thyroxine (T4) and triiodothyronine (T3). These hormones are essential for all cells in the body to function normally.
Hyperthyroidism is a condition of overproduction of hormones, and hypothyroidism is a condition of the underproduction of hormones. Goiter is due to hypothyroidism or hyperthyroidism. The word Goiter indicates an enlarged thyroid and does not mean any malfunction in the thyroid gland. It is a condition that causes the thyroid to grow unevenly. Ref Fig.1
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The Causes of Goiter
As mentioned earlier, Iodine deficiency in the body can lead to goiter. It is the leading cause of goiter. The reason is that Iodine is essential to help our thyroid gland produce thyroid hormones. When you don’t have enough Iodine in your body, the thyroid has to work extra hard to produce the hormones. This extra hard work causes the thyroid gland to grow larger, leading to goiter. The other causes of goiter include the following:
1 – Inflammation - Some people develop thyroiditis which is an inflammation of the thyroid gland. It can cause an enlargement of the gland. E.g. viral thyroiditis
2 – Graves’ Disease - This disease is due to hyperthyroidism. The overproduction of hormones leads to an expansion of the thyroid gland.
3 – Hashimoto’s Disease - Due to this thyroiditis, the thyroid gland is not able to produce enough thyroid hormone, causing hypothyroidism. It causes the pituitary gland to make more thyroid-stimulating hormone causing the thyroid to enlarge.
4 – Nodules - Nodules are solid or fluid containing cysts that may appear on the thyroid and cause it to swell. These nodules are often non-cancerous.
5 – Thyroid Cancer - Cancer may affect the thyroid. It may cause swelling on one side of the gland. It is not very common as the nodules.
6 – Pregnancy can also sometimes cause the thyroid gland to grow in size.
Symptoms of Goiter
The primary symptom of goiter includes swelling in the neck just below Adam’s apple. (Ref Fig.2 below). Apart from this prominently visible sign, the other symptoms are:
1 - A feeling of tightness in the throat region.
2 – Hoarseness or scratchy voice.
3 – Swelling of neck vein.
4 – Dizziness when arms are raised over the head.
Other less common symptoms include difficulty in breathing, coughing, wheezing (due to squeezing of the windpipe), and pain in swallowing (due to squeezing of the food pipe).
Some people have goiter due to hypothyroidism. The symptoms include tiredness, dry skin, constipation, menstrual irregularities, and weight gain.
Some people may have goiter due to hyperthyroidism. In this case, the symptoms include rapid heartbeat, increase in pulse rate, nausea, vomiting, diarrhea, shaking, agitation, and sweating ta room temperature without any exercise.
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Types of Goiter
As you are aware that Goiter has many causes. The type of goiter also depends upon the cause. The different types of goiter (based upon its origin) include:
1 – Colloid Goiter (endemic) - it develops due to a lack of iodine. Iodine is a mineral essential for the production of thyroid hormones. It is common in people living in iodine-deficient areas.
2 – Non-Toxic Goiter (sporadic) – it is unknown but may be caused due to intake of lithium by way of medications to treat mood disorders.
3 – Toxic (nodular or multinodular) Goiter – this type of goiter forms one or more small nodules that produce their own hormones. It causes hyperthyroidism.
FAQs on Goiter
1. What is goiter and what is its most common cause according to the CBSE syllabus?
Goiter is the abnormal enlargement of the thyroid gland, the butterfly-shaped gland located at the base of the neck. As per the NCERT curriculum, the most common cause of goiter worldwide is an iodine deficiency in the diet. Iodine is a crucial element required by the thyroid gland to produce its hormones, thyroxine (T4) and triiodothyronine (T3).
2. What are the main symptoms of goiter that a person might notice?
The primary symptom of goiter is a visible swelling at the base of the neck. Other signs and symptoms can include:
- A feeling of tightness in the throat.
- A cough or hoarseness in the voice.
- Difficulty with swallowing (dysphagia).
- In severe cases, difficulty with breathing (dyspnea).
3. How is goiter typically diagnosed by a doctor?
A doctor can diagnose goiter through several methods:
- Physical Examination: The doctor feels the neck to check for enlargement, tenderness, or the presence of nodules.
- Hormone Tests: Blood tests are conducted to measure the levels of Thyroid-Stimulating Hormone (TSH), T4, and T3 to assess thyroid function.
- Ultrasound: An imaging test that uses sound waves to create a picture of the thyroid gland, revealing its size and any nodules present.
- Antibody Tests: Blood tests can detect specific antibodies that may indicate an autoimmune cause like Hashimoto's disease or Graves' disease.
4. What are the different types of goiter?
Goiters can be classified based on their structure and function:
- Simple Goiter (Diffuse): The entire thyroid gland swells and feels smooth to the touch. It's often caused by iodine deficiency.
- Nodular Goiter: Lumps or nodules develop within the gland, which can be solid or fluid-filled. If it has multiple nodules, it's called a multinodular goiter.
- Toxic Goiter: This type of goiter is associated with hyperthyroidism, where the enlarged gland produces excessive amounts of thyroid hormone.
5. What are the common treatment options available for goiter?
Treatment for goiter depends entirely on its size, cause, and the symptoms it produces. Common approaches include:
- Observation: If the goiter is small and not causing problems, a 'watch and wait' approach may be taken.
- Medications: If caused by hypothyroidism or hyperthyroidism, medications are prescribed to normalise hormone levels.
- Iodine Supplementation: For goiters caused by iodine deficiency, iodine supplements or consuming iodized salt is effective.
- Radioactive Iodine: This treatment can shrink the thyroid gland and is often used for hyperactive thyroids.
- Surgery (Thyroidectomy): Surgical removal of all or part of the thyroid gland is considered if the goiter is very large, causes compression symptoms, or is cancerous.
6. How is goiter related to both hypothyroidism and hyperthyroidism?
Goiter is a physical symptom (enlargement of the thyroid) that can be linked to different states of thyroid function. Hypothyroidism (underactive thyroid) can cause goiter when the pituitary gland releases excess Thyroid-Stimulating Hormone (TSH) to try and force the underperforming thyroid to produce more hormones, causing it to grow. Conversely, hyperthyroidism (overactive thyroid), as seen in Graves' disease, can also cause goiter where the entire gland becomes overstimulated and enlarges.
7. From a biological standpoint, why does an iodine deficiency cause the thyroid gland to swell?
This occurs due to a negative feedback loop in the endocrine system. When dietary iodine is insufficient, the thyroid gland cannot produce enough thyroid hormone. The pituitary gland in the brain detects these low hormone levels and releases more Thyroid-Stimulating Hormone (TSH). TSH's job is to stimulate the thyroid. Continuous stimulation by high levels of TSH causes the thyroid cells to multiply and the gland to enlarge in an attempt to capture more iodine and produce more hormone, resulting in a goiter.
8. What is the key difference between a simple goiter and a toxic nodular goiter?
The key difference lies in their impact on hormone production. A simple goiter is a uniform enlargement of the thyroid, typically due to iodine deficiency, where the gland is not producing an excess of hormones; hormone levels are either normal (euthyroid) or low (hypothyroid). In contrast, a toxic nodular goiter has nodules that act independently of the body's normal regulatory system and produce excessive thyroid hormones, leading to a state of hyperthyroidism.
9. What are 'goitrogens' and is it necessary for everyone to avoid foods containing them?
Goitrogens are natural compounds found in certain foods, like cruciferous vegetables (e.g., cabbage, broccoli, cauliflower) and soy, that can interfere with the thyroid gland's ability to use iodine. However, for a person with adequate iodine intake and normal thyroid function, these foods are perfectly healthy and do not pose a risk. It is generally not necessary to avoid them. They only become a potential concern for individuals with a pre-existing iodine deficiency or hypothyroidism, and even then, only when consumed raw in very large quantities. Cooking these vegetables usually deactivates the goitrogenic compounds.
