The same condition (hypothyroidism) may come on later in life, and after complete removal of the thyroid gland. Such a patient may have to take a certain amount of thyroid every day for the rest of his life. Tumors of the thyroid gland occur frequently in certain areas of the world and often seem to run in families.
Prevention of thyroid trouble is easy today. Iodized salt is available almost everywhere, and in most cases it will prevent the trouble before it starts.
Sources of iodine
The best sources of iodine are sea foods (e.g. sea fish, sea salt) and cod liver oil. Smaller amounts occur in other foods e.g. milk, meat, vegetables, cereals etc. the iodine content of fresh water is small and very variable, about 1-50 micrograms/L
About 90 percent of iodine comes from foods eaten; the remainder from drinking water. The iodine content of the soil determines its presence in both water and locally grown foods. The deficiency is geochemical in nature.
Benefits of iodine
Unique among minerals, iodine has only one known function in the body: It is essential to the thyroid gland for manufacturing thyroxin, a hormone that regulates metabolism in all the body’s cells.
Unlike many other minerals, iodine does not seem to help in the treatment of specific diseases; however, it does play a fundamental role in assuring the health of the thyroid, the butterfly-shaped gland that surrounds the windpipe (trachea). When iodine intake is adequate, our body contains about an ounce of it, and 75% of that amount is stored in the thyroid. This organ controls the body’s overall metabolism, which determines how quickly and efficiently calories are burned.
It also regulates growth and development in children, reproduction, nerve and muscle function, the breakdown of proteins and fats, the growth of nails and hair, and the use of oxygen by every cell in the body.
There is some evidence that iodine derived from an organic source may be effective in reducing the pain of fibrocystic breasts, but patients should discuss this type of supplementation with their doctor first.
By getting enough iodine, pregnant women can prevent certain types of mental retardation in their developing fetus
Deficiency symptoms of iodine
Among the first signs of iodine deficiency, now rarely seen, is an enlarged thyroid gland, known as a goiter. Lack of iodine can cause the gland to expand in an attempt to increase its surface area and trap as much of the iodine in the bloodstream as possible. If your iodine intake is low, your thyroid hormone level may well be low too
Insufficient iodine (which results in too little thyroxin) can lead to such symptoms as fatigue, dry skin, an increase in blood fats, a hoarse throat, delayed reflexes, and reduced mental clarity.
Symptoms of high intake
There is very little risk of iodine overdose, even at levels 10 to 20 times the RDA. However, if you ingest 30 times the RDA, one is likely to experience a metallic taste, mouth sores, swollen salivary glands, diarrhea, vomiting, headache, a rash, and difficulty in breathing. Ironically, a goiter can also develop if you consistently take extremely large amounts of iodine.
We probably get all the iodine we need from our daily intake of iodized salt or from regular servings of seafood. Iodine is also a standard ingredient in many multivitamin and mineral supplements. Even if one is on a severely restricted salt diet for high blood pressure, he or she probably don’t require extra iodine, though they can safely take 150 mcg a day. People on a thyroid hormone should always discuss their condition with a doctor before taking individual iodine supplements.
Some other points
Because iodine deficiency is rare in developed countries, take iodine supplements only if prescribed by your physician.
When iodine is taken with lithium, it may increase the chance of side effects.
Iodine may decrease the effectiveness of some thyroid drugs. Taking high doses of kelp could provide too much iodine and interfere with the actions of some thyroid drugs.
Reminder: If you have a medical or psychiatric condition, talk to your doctor before taking supplements.