Who needs iodine?
Since the nuclear reactor disaster in Japan, countless people have been taking iodine supplements. Many have just been stockpiling against possible need, but a sizable number have been taking mega-dose iodine prophylactically. All scientific sources have stated that those in the continental United States have no significant risks whatsoever from the events in Japan. Nonetheless, people are taking iodine out of panic.
Unfortunately, by taking iodide at the wrong time guarantees it won’t work if it really is needed. Furthermore, 8-10% of the population has latent thyroid problems making them prone to serious side effects from iodide pills.
Adults over 40 are most at risk for iodine side effects and have no clear benefit from using preventive iodine. Many are taking it daily creating no possible benefit yet risk for substantial side effects including stroke and heart attack.
Our thyroid glands depend on iodine to work properly. Since they so aggressively concentrate iodine, they are at risk to concentrate radioactive iodine in the event of nuclear fallout. History has shown that those exposed to low levels of radiation faced much higher rates of eventual thyroid cancer.
Since thyroid cancer takes decades to form, this risk is highest in neonates, infants, children and adolescents, in that order.
Adults under 40 have very minimal risk of thyroid cancer secondary to radiation exposure, yet their risk from iodine per protocol is also low. Adults over 40 face much more risk of iodine side effects than they do benefit even with significant, local exposure.
The rational of iodine loading supplements is that when the thyroid gland is completely full of iodine, it quits absorbing it for a period of time, making it less vulnerable to store radioactive iodine.
Potassium iodide, which supplies 65% iodine, can protect against radioactive iodine, but not other radioactive elements, for a 24 hour window.
When needed, iodine is best given in a single dose, ideally 4-24 hours prior to exposure. Following is dosing per the post Chernobyl World Health Organization Protocol:
|Age group||Single dose of iodine (mg)||Fraction of 100 mg tablet|
|1 month – 3 years||25||1/4|
|Birth – 1 month||12.5||1/8|
People should not take iodine if they have:
- History of thyroid disease
- Active thyroid antibodies
- History of iodine allergy
- Dermatitis herpetiformis
The complicating factor is that many without a known history of thyroid disease do have active thyroid antibodies.
Megadose iodine has also become a fad in the natural health community. Here is a paper I’ve written about the dangers of this practice: goo.gl/xdVDG
Here is the policy paper from the World Health Organization on use of Iodine for radiation exposure prophylaxis. http://www.who.int/ionizing_