Welcome to Brainstuff from house Stuff works dot com where smart happens Him Marshall Brain with today's question, why do they add iodine to table salt? I have a box of salt in the kitchen and it says iodide salt, and then at the bottom it says this salt supplies iodine and necessary nutrient on the ingredient label at lists potassium iodine at a concentration of zero point zero zero six.
A quarter teaspoon of salt or one point five grams therefore provides sixty seven micrograms of iodine, which is about half of the US recommended daily allowance for iodine. The main reason that you need iodine is because of a gland in your neck called the thyroid gland. The thyroid gland produces two hormones, thyroxine and try iodo thyroneine that your body uses during metabolism. Without these hormones, you start
to feel tired, depressed, cold, weak, and so on. Iodine is an important element in these two hormones, so without iodine, your thyroid gland can't produce them. When start for iodine, the thyroid gland also swells up, and when it does it's called a goiter. Groiters can look pretty hideous. Your body doesn't need or contain very much iodine. You might have twenty or twenty five milligrams of iodine in your
entire body right now. However, in some parts of the world, the soil contains no iodine at all, so plants contain no iodine, and therefore iodine deficiency is a big problem. In the US, one part of the country that lacks iodine is the Great Lakes region, So companies started adding iodine to salt in the nineteen twenties to eliminate goiter and thyroid problems. If you lived through the Cold War, you may have heard about the practice of taking iodine
pills during the threat of a nuclear attack. When a nuclear bomb explodes, one substance it forms is radioactive iodine. If you eat, drink, or inhale, this isotope. Your thyroid gland will concentrate it, and this can lead to a thyroid damage or a cancer. By taking an iodine pill, you saturate your thyroid gland with iodine and prevent it from absorbing any of the radioactive iodine. Do you have
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