The thyroid, a small butterfly-shaped gland at the base of the neck, regulates the body's metabolism. The thyroid is unique in that, unlike all other cells in the body, its cells are able to absorb iodine, an element found in food, seawater and coastal soil, reports the Merck Manual. In fact, the thyroid gland needs iodine to produce hormones. Thus, too much or too little iodine can cause thyroid problems, explains the American Thyroid Association.
Iodine Deficiency and the Thyroid
The thyroid can swell up if it is not getting enough iodine, explains MayoClinic.com. The thyroid enlarges in an effort to obtain more iodine. This typically occurs in developing regions far from the ocean, which contains iodine, and is worsened by diets high in food that inhibit thyroid hormone production, such as cabbage and cauliflower. Iodine deficiency is rare in the United States because iodine is added to table salt. In fact, people tend to have too much iodine, which also causes thyroid trouble, in their efforts to insure adequate levels, such as by eating kelp or taking supplements, reports MyThyroid.com.
Treating Thyroid Disease with Radioactive Iodine
Like regular thyroid cells, most thyroid cancer cells have the ability to concentrate iodine. Thus, radioactive iodine is the perfect treatment for thyroid cancer, explains the Merck Manual. The cancerous cells absorb the radioactive iodine, and the radioactivity then destroys them from within. Normal cells are unharmed because they cannot absorb iodine. This treatment is not used for medullary thyroid cancer, because these types of cells are unable to absorb radioactive iodine.
Precautions
Patients who receive radioactive iodine therapy should stay away from babies and children for 4 days, explains the Merck Manual. No precautions are needed regarding returning to work or sleeping in the same bed with someone. However, pregnancy should be avoided for six months after receiving this treatment.
Iodine in Thyroid Scans
To evaluate a growth in the thyroid, a doctor may inject a patient with a small amount of radioactive iodine, which migrates to and concentrates in the gland, reports the Merck Manual. A picture of the thyroid is taken with a gamma camera, which can see radioactivity and produce a picture showing any abnormalities. This picture can also show whether one part of the gland is more or less active than the rest of it.
The Thyroid and Nuclear Accidents
People keep potassium iodine in the medicine cabinet to take in the event of a nuclear accident or attack, reports Thyroid.org. If taken within hours of a nuclear attack, potassium iodide , which is approved by both the Nuclear Regulatory Commission and the FDA for emergency use, can saturate the thyroid with iodine, thus preventing absorption of radioactive material from the air.
