Life Extension Magazine®

Man talking with doctor on risk of radiation health risks

Protect Yourself During a Nuclear Emergency

Japan’s recent nuclear disaster released radioactive isotopes that poisoned the country’s soil, food, and water. With 104 operating reactors in the US, the next deadly release of nuclear material might occur closer to home. Many of the deaths and illnesses from this nightmare scenario result from exposure to iodine-131 radiation and the thyroid cancers it causes. Fortunately, some protection is available with inexpensive potassium iodide tablets.

Scientifically reviewed by: Dr. Shaylind Benson, ND, in August 2023. Written by: Robert Wilkinson.

Protect Yourself During a Nuclear Emergency

The recent nuclear disaster in Japan released radioactive isotopes that poisoned the country’s soil, food, and water.1 The fallout also settled into the Pacific Ocean, where it was rapidly taken up by living things and passed up the food chain.2,3 Some radioactive isotopes remained airborne, eventually reaching more than halfway around the world.4-6

To the surprise of many scientists, America was also exposed to the fallout.

Within days of the event, radioactive contaminants were detected at monitoring stations in the Pacific Coast states.7-9 Nearly 1% of the “hot” sulfur released from the plant is estimated to have traversed the Pacific to reach Southern California beaches.10 By late March, smaller, but still abnormal, levels of radiation were being detected from Washington State to Kansas and even in Florida.7,8

The Fukushima nuclear accident was a health risk not only for the Japanese people but for much of the world. The dangerous effects from this nuclear accident will not be fully known for generations.1 With 104 operating reactors in the US in 31 states,11 experts agree the next deadly release of nuclear material might occur closer to home.

Fortunately, you can take very simple and inexpensive steps to be prepared, and to protect your health. Scientists and the US Government agree that, taken in time, potassium iodide tablets can reduce the hazard from fallout due to radioactive iodine.12

Radioactive Iodine and Your Cancer Risk

Radioactive Iodine and Your Cancer Risk

Iodine-131, known as I-131, is a radioactive isotope commonly released after nuclear power plant disasters. In your body, iodine naturally goes to your thyroid gland, located at the front of your neck.13 The thyroid is your body’s “thermostat,” adjusting your metabolic rate to match your needs. Chemical reactions in your thyroid incorporate iodine into thyroid hormones, which are stored in small globules until needed.

The thyroid’s powerful ability to concentrate iodine is what causes trouble when you come into contact with radioactive iodine-131.14 That radioisotope is a powerful emitter of beta-radiation with a half-life of 8 days.15 Once the iodine is absorbed, the thyroid can be therefore directly exposed to localized tissue-penetrating beta rays at elevated levels for 2-3 months.15

As beta rays zip through thyroid tissue, they smash into any molecule in their way, leaving behind reactive ions. The DNA in your thyroid cells is a major target of beta radiation from iodine-131.16, 17 As it breaks and is repaired, abnormal DNA sequences can arise, producing mutations that lead to cancer.

Thyroid cancer is therefore the most likely malignant outcome of exposure to iodine-131 following a nuclear accident.18 We know this all too well in the wake of the 1986 meltdown and explosion at the Chernobyl nuclear plant in the Ukraine. That event remains the worst nuclear accident in history, exposing more than 5 million people to dangerously high levels of radiation, largely from iodine-131 and radioactive cesium.15,19,20 Much of what we know today about thyroid cancer and radiation comes from long-term studies of those people who were unfortunately exposed.19,21

Humans may inhale iodine 131 if they are directly in the path of the radioactive plume streaming from a crippled plant.22,23 More commonly, they ingest the radioactive material, which gets into groundwater, then grass, and then the milk and meat of cattle that feed on it.15,24 Worrisome levels of iodine-131 were found locally in all of those sources within weeks of the Fukushima disaster.25

Iodine-131 is especially dangerous for children and adolescents, with more than 5,000 known cases of thyroid cancer in those exposed to Chernobyl’s effects in their youth.20,26,27 New cases continue to arise, demonstrating the very long time-scale on which these cancers develop; an excess rate of thyroid cancers in this population is expected for at least several more decades.21,28

Unfortunately, data on adult exposure are limited and inconsistent.21 Although in adults the thyroid gland is less radiosensitive in comparison to children, nevertheless there is evidence to suggest that adults can develop thyroid cancer at excess rates following exposure to iodine-131, but the dose required is considerably higher.18, 29 People who are deficient in iodine at the time of the exposure are at especially high risk, because their thyroids take up the radioactive isotope at twice the normal rate.13,15 Because of the drive to reduce salt intake, a surprising number of American adults have low iodine levels; this relative iodine insufficiency negatively impacts overall health, and is an invitation to thyroid damage in the case of radiation exposure to I-131.30-32

Given the risks for people of all ages, it is wisest to be informed and be prepared. Fortunately, a few simple steps are all you need to take to minimize your risk, and that of your loved ones.

What to Do to Protect Your Thyroid in a Nuclear Power Plant Emergency

One of the most important ways to prepare for a nuclear power plant disaster is to have potassium iodide tablets. Generally, these tablets are quite stable with a typical shelf-life of at least three years, so you can obtain them now and keep them in a safe place until needed.24

Ingestion of potassium iodide tablets is a proven strategy to reduce the risk associated with exposure to radioactive iodine.14 Potassium iodide provides a solid dose of stable, non-radioactive iodine to saturate your thyroid gland.17 You take it only when a credible threat of a radiation leak is announced. Once the stable iodine saturates your thyroid, there’s simply no place for the unstable, radioactive iodine-131 to go, and it is excreted in your urine.33

Today, potassium iodide “blocking” is considered the most effective means of protecting your thyroid from radioactive iodine-131.14 It is the only FDA-approved treatment to reduce the risk of thyroid damage due to radioactive fallout from radioactive I-131. Oral potassium iodide is most effective when administered from up to two days before and up to eight hours after an actual intake of radioactive iodine.13

Radioactivity Risk
Radioactivity Risk
  • Radiation release from a nuclear power plant accident is a clear and present danger, as demonstrated by the events following the earthquake and tsunami in Japan in March of 2011.
  • Large amounts of radioactive material, especially iodine-131, were released from the crippled power station.
  • Iodine-131 causes thyroid cancer.
  • Iodine-131 and other radiation products from the Japanese reactors have been detected at sites throughout the United States and well into Eastern Europe.
  • The continuing operation of more than 100 nuclear power plants in the US makes similar future events all too probable in this country.
  • Potassium iodide, taken up to two days before and up to eight hours following contact with radioactive iodine protects your thyroid gland from cancer.
  • Know the risks and be prepared ahead of time by stocking up on long-lived, inexpensive potassium iodide tablets.

For that reason, disaster management authorities recommend that all people living within a 20-mile radius of a nuclear power plant keep potassium iodide, 130 mg tablets, on hand in quantities sufficient to treat every household member.24, 34

But given the risks, Life Extension® recommends that everyone stock up on these inexpensive, long-lived tablets. Being prepared is crucial. After the recent Japanese nuclear disaster, potassium iodide was in short supply in many countries, including the US, and prices skyrocketed.

Here’s how to use potassium iodide:24,35,36

  1. Obtain 130 mg potassium iodide tablets now.

  2. When (and only when) actual release of radioactive material is announced by official sources, adults should take one pill per day.

    “Adult-sized” adolescents (those weighing more than 150 pounds) should take the adult dose of 130 mg. Children 3-18 should take half a 130 mg tablet, or 65 mg.

    Children 1 month-3 years should be given ¼ of a 130 mg tablet, or 32.5 mg, dissolved in milk, formula, or water.

    Newborns from birth to 1 month should be given 1/8 of a 130 mg tablet (16.25 mg) dissolved in formula or water.

  3. Continue to dose the potassium iodide once daily until risk of significant exposure (by inhalation or ingestion) no longer exists.

What to Do to Protect Your Thyroid in a Nuclear Power Plant Emergency

Potassium iodide has not been found to be dangerous when used just as described.37 It should not be taken on a regular basis as a supplement; the dose of iodine is much too high and excess iodine ingestion on a chronic basis is associated with reduced thyroid function (hypothyroidism) through autoimmune mechanisms.38 During a radiation emergency, however, the FDA has issued this critical guidance: the overall benefits of potassium iodide far exceed the risks of overdosing.36

In addition to keeping potassium iodide available (and accessible), you should follow all food and liquid restrictions issued by the authorities during an emergency. Avoid consuming dairy products and green leafy vegetables harvested in the 3 weeks following a release of radiation (or for as long as officials recommend).24, 25

One final important word of caution regarding radiation disasters. Potassium iodide will protect you from dangerous radioactive iodine-131, a common contaminant released from a nuclear power plant. It does not, however, offer protection against other, longer-lasting, contaminants such as radioactive cesium. These can be released in small quantities from nuclear power plant accidents, and in larger amounts from an actual nuclear explosion or “dirty bomb.” Some protection against these other radioactive isotopes may be derived from the antioxidant supplements that health conscious people take on a daily basis. Those who obtain potassium iodide in their supplements may be afforded a degree of thyroid protection against small amounts of radiation exposure.

Important Update!

As this article was being finalized, the Nuclear Regulatory Commission said that nuclear power plants in the central and eastern United States face previously unrecognized threats from big earthquakes. New seismic studies will be required for all 96 reactors to determine if the plants can withstand the shaking predicted by the governments’s new seismic model.44


The disastrous events of March 11, 2011, at the Fukushima Daiichi nuclear power station in Japan serve as an important wakeup call to the rest of the world. Like it or not, we depend on nuclear power for a large proportion of our energy needs; that won’t be changing any time soon. Further release of radiation from the stricken Japanese plant is by no means impossible. Our own plants, we hope, are less immediately vulnerable, but unforeseen combinations of natural disasters, human incompetence, and even terrorist attacks make radiation release all too real a possibility on our own soil. Many of the deaths and illness among those not immediately in contact with damaged nuclear plants result from exposure to iodine-131 radiation and the thyroid cancers it causes. You can protect yourself today by maintaining a stock of long-lived, inexpensive potassium iodide tablets to take in the event of a nuclear disaster.

Fukushima Daiichi Today: Containment or Cover-Up?

The news from Japan keeps getting worse.

After low-balling initial estimates of radiation releases, the Japanese authorities now acknowledge that substantial amounts of radioactive material leaked from the crippled Fukushima Daiichi reactors.39 The danger zone surrounding the reactors was expanded several times in the weeks following the earthquake, but many Japanese citizens say it still isn’t big enough.39

In fact, many doubt that the government is providing enough information. Local citizens’ groups, armed with personal radiation dosimeters, are fanning out over large swathes of eastern Japan and Tokyo. These groups are finding hot spots surprisingly far from the reactors.39

Reports from Japanese authorities continue to be inconsistent and far from reassuring. In late 2011 a flurry of stories broke, first that the molten material may have reached the last level of containment, threatening a complete breach.40 Such a breach could mean a massive release of radioactive material is still to come.

Days later came a report that at least 45 tons of highly radioactive seawater had leaked from the power station, at least some of it reaching the ocean.41

Despite these reports, on December 14, 2011, the Japanese government declared control of the plant’s still-overheating reactors — to immediate condemnation by experts.42 Those critics point out that the actual situation within the plant remains unclear, with hot fuel still potentially burning its way out of the containment vessel. Another earthquake, or failure of the temporary cooling system now in place, could spell new disaster, those experts say.42

At last report, the Japanese government was predicting a 40-year-long cleanup effort, acknowledging that some of the robotic technology required had still to be invented.43 The unknowns surrounding this delicate, decades-long procedure make it all the more urgent to keep radiation-blocking potassium iodide tablets on hand, should the unthinkable happen.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.


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