The thyroid gland absorbs iodine while helping regulate metabolism and other bodily functions. Thyroid cancer occurs when thyroid cells grow rapidly, destroying surrounding tissues. While low iodine levels have been linked to thyroid dysfunction, it is not believed to directly cause thyroid cancer. If you have symptoms of thyroid cancer, consult a physician before making dietary changes.
Sources
Once a common condition, iodine deficiency is now rare in most developed nations. A majority of the iodine in the diet comes from iodized salt, though it is also present in kelp, shellfish and breads made with iodate dough. The thyroid gland uses iodine to produce hormones like T3 and T4 that control metabolism and other functions. According to the American Cancer Society, radioactive iodine therapy is the standard treatment for metastatic follicular thyroid cancer and has been shown to increase survival rates in people diagnosed with this condition.
Causes
In many cases, the cause of thyroid cancer is not known. Risk factors like family history of thyroid cancer and radiation exposure may increase your risk somewhat, according to MayoClinic.com. Frequent head and neck X-rays expose the thyroid to radiation, which can increase your risk over time. Goiter -- a type of noncancerous thyroid growth -- is another known risk factor for thyroid cancer. While lack of iodine does not directly cause thyroid cancer, it has been linked to goiter, which in turn increases your risk of developing the disease.
Symptoms
The symptoms of thyroid cancer vary depending on the type and stage of the disease. It often causes no noticeable signs until it has grown or spread to other locations. MayoClinic.com lists difficulty swallowing, swollen lymph nodes in the neck and throat pain as possible symptoms. Because these may also be signs of other conditions, a proper diagnosis is needed for effective treatment. Hoarseness and a lump in the neck may also signal thyroid cancer in some cases.
Prevention/Solution
Since the cause of thyroid cancer is unknown, there is little that can be done to prevent it. Eating a healthy diet rich in iodine and other nutrients can help maximize thyroid function, though it is not known to influence cancer risk directly. If you live near a nuclear power plant, you may be eligible to obtain potassium iodide, a medication that protects the thyroid in the event of a nuclear disaster. Because excessive iodine intake can be harmful, consult your doctor before taking an iodine supplement.
