Why are iodine tablets distributed during nuclear emergencies?
Iodine's impact on the thyroid and metabolism
Iodine tablet usage generally spikes in the wake of a radiation exposure, similar to those at Japan's nuclear reactors or Chernobyl. In these cases, people look to iodine tablets because potassium iodide (KI) the active ingredient in these pills, gets stored in the thyroid and prevents any ingested radioactive iodide from getting absorbed where it can cause damage. Radioactive iodine, or iodine 131, can cause severe damage to the thyroid when it gets absorbed. In the same way that people with thyroid disorders may take radioactive medication to disable the thyroid, healthy people should likewise take precautions to keep this from happening, since people with thyroid disorders who needed radiation therapy need to take pills to supplement the metabolic functions for which the thyroid is responsible. The problem with radiation ingestion when it contains iodine 131 is that the amount of radiation could not only destroy the thyroid but also lead to cancer. Although iodine pill therapy does not protect against the effects of radioactive iodine elsewhere in your body, it gets concentrated in the thyroid instead of getting filtered from your body through the kidneys.
People buy thyroid pills to deal with the eventuality of radiation exposure, whether it is from an atomic accident like the Japan meltdown, or through an attack where iodine would also be released. People who purchase iodine tablets should be aware that they should only be taken when there is a real danger of exposure, and in those cases on the advice of health authorities. The side effects of iodine pill supplements can cause problems of their own, such as swelling, hypothyroidism, and issues in children, young adults, and the elderly. Healthy people in some age groups may only need it in extreme cases. This fact sheet from the CDC may help you determine the dosage of iodine pills and whether you should take them at all.
New intereste in iodine tablets came in the form of a US goverment order for 14 million iodine pills, which may either be a coincidence or preparation for an unusual occurence.
Notes and Special Information
Special note: The use of iodide tablet supplements should only be done under the supervision of medical authorities. There can be some serious side effects.