Goiter is the term used to describe the thyroid gland which has become enlarged. Large goiters can make it hard to breathe or swallow and can cause a cough and hoarseness. There are many conditions leading to its enlargement; namely, iodine deficiency, autoimmune disease, inflammation, new growth and other causes.
Goiter occurs much more frequently in women than in men. Worldwide, the most common cause of goiter is iodine deficiency which can be prevented by the appropriate intake of food rich in iodine (salt-water fish, crabs, shrimps, squid, seaweeds) and others; and by the regular use of iodized salt in daily diet.
Dr. Teofilo O.L. San Luis, Jr., chairman of the Philippine Thyroid Council, explains that salt is the best vehicle for adding iodine. Everyone needs salt, everyone eats it, usually in daily amounts, and the technology for iodization is straightforward. The Philippines has regulations calling for 20-40 mcg iodine/g of salt (20-40 ppm); thus if an individual eats 5 g of salt iodized at 30 ppm, he/she gets 150 mcg iodine from this source alone.
Another method for providing iodine to a community is through the administration of iodized vegetable oil. A single administration orally provides adequate iodine for about a year, and if given by intramuscular injection, is satisfactory for about three years. Iodized oil is most useful when the iodine deficiency is severe, when immediate correction is important, and when iodized salt is not available (or its iodine concentration is below recommended levels).
Drinking water is another occasional vehicle for iodine nutrition. Some systems slowly release iodine from a porous basket. Another approach adds an iodine solution to water in a well or flowing through a pipe. A simpler version merely adds a few drops of a concentrated solution manually to vessels containing drinking water in a school or home. If iodine (I2) is added, it can also sterilize the water; this property is useful because many regions with iodine deficiency also have contaminated food and water.
Occasionally, iodine is given as tablets of potassium iodide, from 100 to 300 mcg per day or about 1 mg per week. Some vitamin/mineral preparations for daily use contain 150 mcg iodine, the recommended amount. Other vehicles like sugar, bread, and tea have been occasionally used for iodine delivery. However, the many advantages of iodized salt make it the overwhelming favorite for most countries.
Dr. San Luis said that for goiters due to other causes, they can be treated medically (by anti-thyroid drugs or thyroid hormones as the case may be), surgically, or through radioactive iodine depending on the clinical situation. Goiters with lumps (or nodules) can be the beginnings of thyroid cancer which would require surgery followed by radioactive iodine ablation.
Analysis of the symptoms and a physical examination (usually centered on the neck) is done by a physician or a health worker. These should alert them that something is wrong with the iodine nutrition of the patient causing goiter. Some laboratory tests (called thyroid function tests: TSH, T4, T3, FT4, FT3, thyroid antibodies); or imaging procedures (thyroid scan, ultrasound) are requested to confirm the suspicion of a goiter. In certain instances, a fine-needle aspiration biopsy (FNAB) is done to determine if there inflammatory thyroid disease or thyroid cancer.