Do radiation-nullifying pills actually work?

Dear Cecil: What’s the gig with these radiation-nullifying pills I’ve heard about? They supposedly build up the body’s defense mechanisms against plutonium particles and the like. I’d rather munch pills than don a lead rain jacket. Do the pills work? If so, where could I score a bag? C.F., Los Angeles

Cecil replies:

You’d like to think this sort of thing was a quaint vestige of the Cold War, but what with India and who knows who else testing nuclear weapons, maybe we’d better brush up. Amazingly, antinuke pills are one of those screwball survivalist gimmicks that may actually help. Nuclear fallout contains radioactive iodine, which the body mistakes for ordinary iodine and absorbs into the thyroid, where it sticks around long enough to poison you. To prevent this, you can take a dose of a benign chemical called potassium iodide (KI) before a nuclear attack. This swamps your thyroid with good iodine, preventing the radioactive version from being absorbed. The Food and Drug Administration says potassium iodide is safe and effective and recommends that civil defense officials include it in their emergency planning. Note that KI won’t cure radiation poisoning, nor will it prevent radiation injury from sources other than radioactive iodine. In a survivalist magazine some years ago I saw an ad offering a “doublepack” of KI (supposedly enough for two adults) for $10 plus $2 shipping. At the time $12 struck me as a little steep; if I were you I’d shop around. Sure, it’s a nuclear holocaust we’re talking about, but that doesn’t mean we can’t be thrifty.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.