There's no evidence to support the claim that drinking water with fluoride has benefits to our oral health. Just take a look at the World Health Organization chart on fluoridated vs. non-fluoridated countries. —Mia N.

It's funny you should cite the WHO as a source. I happen to have right here its gripping 134-page "Fluoride in Drinking Water," which states—and I quote—"Fluoride has beneficial effects on teeth at low concentrations in drinking water."

It's not difficult for an uninformed layman to go on the Internet and find evidence that fluoride kills. (In fact, the less well-informed you are, the easier it is!) It's also not difficult to go on WebMD and convince yourself you have cancer.

Much of the confusion seems rooted in the fact fluoride occurs naturally in some groundwater, sometimes in high enough doses to cause health problems. Most credible sources cited by fluoride opponents (including this WHO report) are talking about this, not about low-dose public fluoridation programs.

But who needs appeals to authority, anyway? We can do the science ourselves!

About 200 million Americans have fluoridated water today, and the program began in 1945. That's, conservatively, 250 million people, over four generations. With apologies to the Centers for Disease Control and Prevention, I believe this represents the largest clinical trial in human history, by about three orders of magnitude.

So, show me the bodies—if fluoride is deadly, there should be thousands! Show me the mutant kids with three arms and gills, scrabbling through the rubble of our once-proud civilization, and I'll believe in the fluoride apocalypse.

Maybe the folks who dreamed up fluoridation in the '40s were taking a chance, but I'd say we've dodged the bullet. Anyway, when it comes to planet-dooming perils, we've got bigger fish to fry.