So what’s all the potassium iodide hype about?

Hawaii sells out of potassium iodide pills in the aftermath of Japan's nuclear disaster

Jade Eckardt

Food Smarts
with Jade Eckardt


I spent last week’s tsunami scare in the boonies of Lower Puna on Hawaii Island. Being in one of the few houses in the area on County water, we filled up a few gallons of water, and, well, that was it. We didn’t rush into Hilo to join the toilet-paper-buying frenzy that was reportedly causing chaos at Walmart.

It’s rare that we get a thrill out of an impending disaster, but I did manage to get a true highlight moment out of it. Sitting in the Puna jungle in a house silent except for the infinite number of coqui frogs chirping, I suddenly heard virtually every single chirp stop. Immediately, I thought, “Uh oh, something heavy is gonna go down.” Five seconds later the house shook with the 4.5 earthquake. A few seconds after that, every frog began chirping in unison.

I’d heard about this before: animals running inland in Thailand before the tsunami, animals going quiet before eclipses and other natural disasters. But I was personally thrilled to experience it myself.

Anyway, on Monday I was headed to the airport to fly back to Oahu after days of being out of the loop with the Japan disaster. A friend calls me and says, “So, I heard that taking potassium iodine pills can help prevent damage from the radiation headed our way from Japan. The whole Big Island is out. Could you find some on Oahu and send them to me?”

Sure I said, and asked for the rundown on what this iodide radiation thing is all about. (On a side note, it’s common for “Big Islanders” to think that Oahu always has everything a person can’t get on the “Big Island.”)

So with my son strapped into his car seat behind me, my newest inspiration to be overly cautious, I pulled over and started calling Oahu health food stores. Celestial Natural Foods in Haleiwa was out of the pills. Down to Earth in both Pearlridge and Honolulu said they were out for one to two weeks, but were “hoping to get them as soon as possible.” Whole Foods Market was also out, and said, “Most ‘mainland’ distributors are out because of the Japan situation too.”

Last resort, Vim and Vigor in Honolulu. You guessed it: Out.

A guy at Down to Earth in Honolulu offered to put me on a waiting list, which I gave him my name and number for. Again, thinking of my one-and-a-half-year-old son, my normally no-worries-nothings-going-to-happen self text messaged family in New York City and Long Island. “Hey, can you find me some potassium iodine pills?” Long story short, Long Island couldn’t cough up one bottle of the pills, with pharmacists telling my cousin people were sending them to the West Coast. I’d like to point out that Long Island is a really big island with lots of health food stores, and lots of pharmacies.

So what’s all the potassium iodine hype about? In a section on their website titled “ABCs of Japan’s Nuclear Reactor Disaster,” the Union of Concerned Scientists (UCS), a science-based nonprofit working for a healthy environment and a safer world, has a pretty good explanation of how potassium iodine can help prevent damage on the human body from nuclear radiation.

According to the UCS, radioactive materials decay and release particles that can damage living tissue and lead to cancer. Some elements have different forms, called isotopes, that differ in the number of neutrons in the nucleus. The radioactive isotopes of greatest concern in a nuclear power accident are iodine-131 and cesium-137. Iodine-131 has a half-life of 8 days, meaning half of it will have decayed after 8 days, and half of that in another 8 days, and son on. Therefore, it is of greatest concern in the days and weeks following an accident. It is also volatile, meaning it will spread easily.

In the human body, iodine is taken up by the thyroid, which is located in the neck, just below the Adam’s apple, and becomes concentrated there, where it can lead to thyroid cancer in later life. Children who are exposed to iodine-131 are more likely than adults to get cancer later in life. It was a major contributor to health problems after the Chernobyl disaster.

To guard against the absorption of iodione-131, the UCS says people can proactively take potassium iodine pills so the thyroid becomes saturated with non-radioactive iodine and is not able to absorb any iodine-131.

Cesium-137 has a half-life of about 30 years, so will take more than a century to decay by a significant amount. Living organisms treat cesium-137 as if it was potassium, and it becomes part of the fluid electrolytes and is eventually excreted. Cesium-137 is passed up the food chain. It can cause many different types of cancer.

It’s important to not over do it when taking iodine, as there are risks and side effects.


If you can get your hands on some, how much iodine should you take, and how often?

According to the FDA:

* Adults, including women who are breastfeeding, should take 130 milligrams of stable iodine.

* Children aged 3-to-18 should take 65 milligrams. Children who weigh more than 150 pounds should take the adult dose, regardless of age.

* Nursing and non-nursing infants between 1 month and 3 years of age should take 32 milligrams.

* Nursing and non-nursing newborns should take 16 milligrams.

According to an article in the National Post, usually one dose of iodine, which protects the thyroid gland for 24 hours, is all that is needed. Officials may request that the public take a dose of stable iodine every 24 hours for a few days if radioactive iodine will remain in the environment for a prolonged period of time. Pregnant and breastfeeding women and newborns should avoid taking multiple doses.

It’s important to not over do it when taking iodine, as there are risks and side effects.

* When officials advise the public to take iodine pills following a nuclear event, the benefits outweigh the risks.

* Taking a higher dose than is recommended will not provide more protection and can cause severe illness or death.

* People with thyroid disease should take iodine pills only under a doctor’s supervision.

* General side effects include intestinal upset, rashes, and inflammation of the salivary glands.

* An overdose of iodine can cause the thyroid to shut down completely. 

Many people in Hawaii are still ordering potassium iodine online, so if you’re motivated you can try that. Otherwise, there’s always the waiting list at Down to Earth. What about my family’s search in New York City? Well, my aunt has found what may be New York’s only bottle in her personal emergency kit, and it’s in the mail.


Related Stories:

Potassium iodide pills widely sought

Experts advise against taking unnecessary potassium iodide

Presidential press briefing by Press Secretary Jay Carney on March 15