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Name: Theresa
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Why do they put iodine in salt?

Iodine was introduced into salt at earlier this century when it was discovered that certain areas of the US had a mark deficiency in iodine in the diet of people, and people developed a neck swelling (goiter). The Great Lakes region is one of these areas where the soil is lacking iodine. Goiter can be caused when the thyroid gland swells because of a lack of iodine in the diet. Most medical advise now states that iodine in salt is no longer necessary due to our food sources arising from all over the world.

Steve Sample

Hi Theresa...see, there are a variety of elements and compounds that are necessary for the proper maintenance of our life. One of these is iodine, since a small quantity of iodine is needed for the adequate functioning of the thyroid gland. A deficiency of iodine produces dire effects, as goiter, where the thyroid gland swollens due to the lack of iodine traces in the diet. The iodine affects directly the tyrhoid gland secretions, which themselves, to a great extent, control heart action, nerve response to stimuli, rate of body growth and metabolism.

Iodine is available in seafood, and goiter (or goƮtre) used to be found particularly in montaineous regions and areas far from salt water. Prevention of iodine deficiency is most simply done by eating seafood regularly or by the use of iodized salt.

To overcome iodine deficits, government health officials in many countries have made dietary iodine additives (in table salt) mandatory. A lack of iodine during infancy may cause a condition known as cretinism, in which mental and physical de- velopment is severely impaired. this condition can be prevented by a food diet with adequate iodine, during pregnancy.

So when you salt your food, not only you make it tasty, but you are giving to your body the essencial sodium chloride that supplies the chloride ion, necessary for the production of hydrochloric acid by our stomachs, and the sodium ion necessary to maintain the proper balance between sodium and potassium ions that has great physiological significance. And...also the two cents of iodine, of course... Thanks for asking NEWTON!


Hello Theresa

In some areas of the world the soils are deficient in iodine and consequently crops and people's diets are deficient in iodine. Low iodine affects the thyroid gland which requires iodine in order to produce thyroid hormones which play a role in growth and metabolism. The thyroid becomes enlarged to compensate resulting in a condition called goiter.

In order to reverse this problem iodine is added to salt. This is the case in the USA and was the case in Australia (where I live) until recently. We have stopped using iodised salt (although it is still available) because our diet is much more varied than it used to be. Consequently we can now do without the extra salt.

Thanks for the question

Cameron Millsom

Iodine is an essential human nutrient, vital to the proper function of the thyroid gland (it is a necessary ingredient of thyroid hormone). If a body is denied iodine, the thyroid swells up, causing a goiter. Putting iodine in salt prevents this from happening - it's just like enriching flour by putting in vitamins.

Rich Barrans

Iodine is necessary for proper thyroid function. If you don't get enough iodine, your thyroid works overtime and you get a big thing on your neck called a goiter, which is a swollen thryoid. (Your adam's apple is actually your thyroid-its in your neck-you can feel it going up and down when you swallow)I was always told that sea salt contains iodine. Anyway-the soil in the regions near the sea contain iodine naturally because of the ocean water. But when you come inland, the salt in the ground doesn't contain iodine. So they add iodine to salt to prevent goiter.

Van Hoeck

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