ENLARGED THYROID GLAND

WHAT IS GOITER?

A goiter is an enlarged thyroid gland.

The thyroid gland is situated in front of the windpipe and is responsible for producing and secreting hormones that regulate growth and metabolism.

Most cases are categorized as ‘simple’ goiters that do not involve inflammation or any detriment to thyroid function, produce no symptoms, and often have no obvious cause.

Some people experience a small amount of swelling. Others can have considerable swelling that constricts the trachea and causes breathing problems.

SYMPTOMS

The degree of swelling and the severity of symptoms produced by the goiter depends on the individual.

Most goiters produce no symptoms. When symptoms do occur, the following are most common:

• throat symptoms of tightness, cough, and hoarseness
• trouble swallowing
• in severe cases, difficulty breathing, possibly with a high-pitch sound

Other symptoms may be present because of the underlying cause of the goiter, but they are not because of the goiter itself. For example, an overactive thyroid can cause symptoms such as:

• nervousness
• palpitations
• hyperactivity
• increased sweating
• heat hypersensitivity
• fatigue
• increased appetite
• hair loss
• weight loss

In cases where goiter is a result of hypothyroidism, the underactive thyroid can cause symptoms such as:

• cold intolerance
• constipation
• forgetfulness
• personality changes
• hair loss
• weight gain

Aside from the swelling itself, many people with goiter present no symptoms or signs at all.

CAUSES

Goiter can be caused by a number of different conditions:

Iodine deficiency

Iodine deficiency is the major cause of goiter worldwide, but this is rarely a cause in more economically developed countries where iodine is routinely added to salt.

As iodine is less commonly found in plants, vegan diets may lack sufficient iodine. This is less of a problem for vegans who live in countries such as the United States that add iodine to salt.

Dietary iodine is found in:

• seafood
• plant food grown in iodine-rich soil
• cow’s milk

Autoimmune disease

The main cause of goiter in developed countries is autoimmune disease. Women over the age of 40 are at greater risk of goiter, as are people with a family history of the condition.

Hypothyroidism is the result of an underactive thyroid gland, and this causes goiter. Because the gland produces too little thyroid hormone, it is stimulated to produce more, leading to the swelling.

This usually results from Hashimoto’s thyroiditis, a condition in which the body’s immune system attacks its own tissue and causes inflammation of the thyroid gland.

Hyperthyroidism

Hyperthyroidism, or an overactive thyroid gland, is another cause of goiter. Too much thyroid hormone is produced. This usually happens as a result of Graves’ disease, an autoimmune disorder where the body’s immunity turns on itself and attacks the thyroid gland, causing it to swell.

OTHER CAUSES

Less common causes of goiter include the following:

• Smoking: Thiocyanate in tobacco smoke interferes with iodine absorption.
• Hormonal changes: Pregnancy, puberty, and menopause can affect thyroid function.
• Thyroiditis: Inflammation caused by infection, for example, can lead to goiter.
• Lithium: This psychiatric drug can interfere with thyroid function.
• Overconsumption of iodine: Too much iodine can cause a goiter.
• Radiation therapy: This can trigger a swollen thyroid, particularly when administered to the neck.