Nuclear plant explosions in Japan released massive columns of smoke into the air. According to officials, 230,000 units of iodine have been distributed to evacuation centers near the nuclear power plants as a precaution. So, why is Japan distributing iodine tablets?

Thyroid Effects

After the 1986 Chernobyl disaster, thousands of cases of thyroid cancer were reported in children and adolescents exposed to radiation. Following a radiological or nuclear event, escaping radioactive particulates consisting of radioactive iodine-131 can enter your body via contaminated air, food, or water (referred to as “internal contamination”).

When internal contamination occurs, your thyroid gland quickly absorbs the radioactive iodine and can cause thyroid cells to die or mutate. In fact, radioactive iodine is used therapeutically to purposely destroy the thyroid when cancer is present or when the gland no longer functions properly.

How Iodine Tablets Help

The thyroid gland requires iodine to function.

Potassium iodide, also called KI, is a salt of stable (not radioactive) iodine which is available through the food you eat. You need iodine to make essential thyroid hormones which are needed by every cell in the human body.

According to the Centers for Disease Control and Prevention (CDC), KI is used as an emergency response to radiation exposure to prevent the thyroid gland from taking in the radioactive iodine. The thyroid can’t tell the difference between radioactive and stable iodine and will absorb both. The tablets work by “filling up” your thyroid with KI, so it can’t absorb any more iodine for the next 24 hours.

Degree of Effectiveness

Iodine tablets don’t provide 100% protection against radiation exposure. It can only protect the thyroid from radioactive iodine. That is, it doesn’t protect other body parts (such as the stomach, intestines and bone marrow which are also highly vulnerable) nor does it block other radioactive elements.

How well the iodine tablets work depends on several factors, such as:

  • How soon you take the tablets after contamination
  • How quickly the KI is absorbed into your bloodstream
  • How much radioactive iodine is already present in your thyroid

Will iodized table salt work as a substitute?

Iodized table salt contains iodine from the KI that’s added to it, but it doesn’t contain enough iodine to block radioactive iodine from getting into your thyroid gland. It is NOT a substitute for KI.

Karen Owoc

Karen Owoc is a certified Clinical Exercise Physiologist specializing in cardiopulmonary rehabilitation and lifestyle medicine. Her science-based approach to longevity, nutrition, and muscle health has made her the go-to source for health seekers and medical professionals alike. Karen's best-selling book on functional longevity, "Athletes in Aprons: The Nutrition Playbook to Break 100", and her transformative perspective have mended many minds, hearts, and spirits.