Millions of North Americans are suddenly aware of potassium iodide (PI) since Japan's nuclear plants started spewing out radioactive material. But how much will PI protect us from radioactive particles? Who should take it, and who should not?

During a nuclear explosion or meltdown, radioactive iodine (I-131) enters the atmosphere and it has a malignant effect on the thyroid gland.

The thyroid normally obtains iodine from iodized salt and shellfish to produce the hormone thyroxin. This hormone acts much like the accelerator of a car, controlling heart rate, temperature and energy level. Too much of it causes hyperthyroidism and too little, hypothyroidism.

But the thyroid gland isn't particular where it obtains iodine. It also has no way of distinguishing between radioactive I-131 from normal iodine. So when radioactive I-131 enters the atmosphere, the thyroid takes what's offered and absorbs I-131 as well. Fortunately, potassium iodide is extremely effective against I-131 and works as a blocking agent. PI quickly saturates the thyroid with ample amounts of good iodine, leaving no room for radioactive I-131.

But what doesn't potassium iodide do? There's a general misconception among the public that PI will protect the entire body from radiation. It doesn't. Rather, PI's role is to prevent the development of thyroid malignancy and has no effect on preventing other cancers. Nor does it have any power to prevent radioactive material from entering the body, or to nurse an injured thyroid gland, or other glands back to normal.

Unfortunately, there's no magic radiation antidote, the be-all-and-end-all, to protect us from all forms of radiation exposure. Nor does PI strengthen our immune system against radioactive material.

From a personal standpoint, I have a major interest in nuclear fallout, as I live in Toronto, a relatively short distance from Pickering's nuclear plant. So should I rush out and purchase potassium iodide? To find out, I called several pharmacies to see if I could purchase PI. I was in for a few surprises.

Some pharmacists replied that they were not certain if a doctor's prescription was needed, while others said that it was. At the end of many calls, none had PI capsules to sell, with or without a prescription. But PI could be ordered and this would take two days. So if Pickering blew up while I was writing this column, I would be in deep do-do. There are just too many unanswered questions to do me much good.

Sources in the U.S. told me that some states have stockpiles of PI. But no terrorist worth his salt is going to announce the date of an attack. Nor will there be any advance warning if an earthquake strikes Pickering. Moreover, PI should be taken two hours before exposure to I-131. In the confusion and terror that strikes following a radioactive blowout, it's highly unlikely people would get this protection handed to them. And how many will have enough foresight to try and purchase PI before a nuclear disaster?

People who have an allergy to iodine or shellfish should not take PI. And it's vital to never consume tincture of iodine. This could be fatal. The poison warning on the bottle is there for a good reason.

For the moment, it appears that radioactive material is not going to cross the Pacific from Japan. In fact, authorities say even if it does, the level of activity will be so small that it will not endanger life.

Let's hope that no other disaster strikes where a country has to face radioactive material. But if it does happen, we will all need more than PI. In addition to I-131, a nuclear disaster emits 400 other radioactive particles to contaminate the air, food and water that could end our lives. So just hope you're at the North Pole with a southerly wind blowing.

Last week's column discussed Sytrinol, a natural cholesterol-lowering remedy. Since then, many readers have asked where it can be obtained. Preferred Nutrition Sytrinol is available at most health food stores. Or call the toll-free number 1-888-826-9625 to locate one.


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