The Los Angeles Times reports sales of Geiger counters and potassium iodide in the United States are skyrocketing:
Sales of Geiger counters and potassium iodide supplements that can block some radiation have surged nationwide since Friday, fueled by concerns among some Americans that radiation released from Japanese nuclear plants could spread to the United States.
Yet, it seems potassium iodide doesn't really do much to help:
Despite those statements, potassium iodide supplements — which can protect the thyroid gland if taken before or shortly after a person is exposed to radiation but do not protect other body parts or prevent damage from other radioactive substances — are either sold out or selling quickly at several Chicago-area stores.
Leaving aside the question as to whether any noticeable radiation will affect the United States (most experts say it won't), is the protection of the thyroid gland offered by potassium iodide really effective? Is it useful in light of the fact that it doesn't seem to protect the remainder of the human body?