The extensive media coverage of the nuclear crisis in Japan, as well as the even more extensive reactions to it reverberating through cyberspace, suggest to me that there is fairly widespread confusion about both the risks of radiation, and the specific defense afforded by iodine supplementation. Drawing on general medical knowledge, rather than any dedicated expertise in radiation medicine, I write to clarify.
1) Thyroid hormones are manufactured by the thyroid gland using iodine. I believe it is commonly known that long-standing iodine deficiency leads to goiter, and hypothyroidism. In fact, goiter is still common in many parts of the developing world, and the World Health Organization supports an iodine distribution program to help combat that problem.
2) The thyroid gland can develop several kinds of cancer, and is more vulnerable to cancer to many other body sites because of its generally high rate of metabolic activity. Thyroid cells are especially vulnerable to the effects of radiation.
3) Nuclear fission reactions using uranium or plutonium release a variety of radioactive 'breakdown' products, and among these is radioiodine. There are several varieties of radioactive iodine, but I-131 tends to predominate.
4) The thyroid gland cannot distinguish between stable and radioactive iodine, so take up any available radioiodine just as assiduously as its stable counterpart. This is used under controlled medical conditions to treat disorders of the thyroid -- but under the uncontrolled conditions of a nuclear plant failure, I-131 exposure will potentially cause low-level radiation injury to thyroid cells -- enough to damage, but not kill them. Such injured cells are prone to develop cancers over time.
Iodine supplementation -- specifically the use of potassium iodide -- is potentially protective in two ways. First, if the the thyroid gland is saturated with stable iodine, it is less prone to take up any radioiodine because, in crude terms, there is no room at the inn.
Second, while iodine is essential for thyroid function and deficiency can cause hypothyroidism, high-dose iodine intake can actually cause hypothyroidism as well. This seemingly paradoxical response is called the Wolff-Chaikoff effect, and involves several mechanisms -- including suppression of the manufacture of thyroid hormones from the available iodine. It lasts only a short time, but for that time it will block the uptake of any more iodine into the gland.
I hasten to add that there is no reason for anyone in the U.S. to be taking iodine supplements to defend against radiation from the Japanese leak at this point; no meaningful risk currently exists here. And, there are two precautionary notes to sound. The first pertains to the 'well, it couldn't hurt' approach. Actually, it could -- if iodine is supplemented after exposure to radioiodine, there is some possibility of it slowing thyroid function, and causing the radioactive iodine to remain in the gland longer. Second, iodine supplementation protects the thyroid gland only; it does not provide any kind of total body defense against the effects of radiation.
The iodine defense works against the threat of I-131, and the Japanese in the affected area should be using it. We in the U.S. should not. But we should understand it, so it's there for us if ever we need it. I certainly hope we don't.
Dr. David L. Katz
Follow David Katz, M.D. on Twitter: www.twitter.com/DrDavidKatz
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The panic over the radiation hype just goes to prove that people are as stupid as they were 40,000 years ago......they react irrationally and emotionally rather that go on line to get the real facts on radiation poisoning.
http://tinyurl.com/48xn2ad
Morton's Iodized Salt, $0.99, Walgreens.
Here lies only confusion.
For example, as a result of today’s toxic environment, particularly with respect to toxic halides that compete with iodine (fluoride, bromine, chlorine), daily doses as much as 100 times the RDA (150 ug) are necessary for most people to maintain health. Interestingly, the Japanese have been ingesting these higher levels for generations (average of about 13 mg). High dose iodine, properly used, has resolved hypothyroidism, hyperthyroidism, and Hashimoto’s thyroiditis.
The statement that iodine supplementation will only protect the thyroid from radiation is also likely wrong. It is now known that in the female, the breasts and ovaries are large iodine consumers, and supplementation may also protect those areas of the body.
For the latest recommendations on iodine intake in view of the radiation risk, see:
http://drdavidbrownstein.blogspot.com/
Additional information can also be found in “The Wellness Project.”
Roy Mankovitz, Director
http://www.MontecitoWellness.com
A research organization
I had a goiter sticking out of the side of my neck for 10 years and not ONE DOCTOR ever mentioned iodine. I lost TWENTY YEARS OF MY LIFE, the most productive ones because medical science didn't believe in iodine supplementation - all while the Japanese consume up to 80 miligrams of iodine everyday in their diet.
It should be understood that Dr. Mankovitz and Dr. Brownstein are renegades in the medical community and don't prescribe to the prevailing idiotic notions that we should only have 150 micrograms of iodine - which isn't nearly enough.
I am getting tired of medical science, which has a lousy track record despite the heroics and exclusive of emergency trauma care, telling us man can triumph over nature. That is stupidity. As is to leading readers to believe it is "only the thyroid" affected by radioactive fallout. The message is "bring on the fallout, we have iodine" - a moronic chant at best. Our entire bodies, our entire environment, is very adversely affected by radiation, oil spills, pollution, and our lousy food supply, yet we have big pharma and the ama in the wings telling us all is well.
Also...watch old equipment.particularly in dentist and ortho offices, older machines leak more. Some of the machines in socialized medicine leak...I am fearful someone will get microwaved,
I take anywhere from 1-4 Iodoral tablets (available on amazon) and there's lots of info on this every day. Been doing this for over a year and I feel great. My reasons for taking it are many. More than 90% of us are low in iodine. Some forms of iodine are harmful. Iodoral is not. All of us need a combination of iodine and iodide, the two forms of iodine used throughout our bodies. Iodoral and Lugol are the only supplements containing these two nutrients. Lugol, however, tastes foul. Hence, why I happily take Iodoral and feel great. Look at the reviews on amazon. There's a book about it also. Google it. Do your research.