Thursday, December 02, 2004

Not the Tooth Fairy

Why keep coming back to a blog that is absolutely predictable? If all this site did was regurgitate things we collectively believed, why bother? The good news is that I have a solid contrarian streak in me unlikely to be predictable. That means some people will come here expecting certain opinions and find something else. Life is risky.

Here's what I plan to do in this post: Raise a question about what CDC calls one of the "ten great achievements in public health in the 20th century," fluoridation of drinking water to prevent dental caries. Warning to young public healthies: Don't try this at home! This is a sure-fire career killer. Leave it to grizzled old geezers like me who have nothing to lose.

This is not an anti-fluoride rant (sorry to some of you). Nor is it a pro-fluoride rant (sorry to some more of you). Most of you probably never think about fluoride (so here's your chance). Don't ask me who are the red-staters and who are the blue-staters in this; this is one of those cross-cutting issues. I can tell you one thing: both sides are FUCKING CRAZY on this subject. Since you don't know my name I'll worry less some crazed dentist will break into my house to try to disembowel me or some equally crazed anti-fluoridationist try to sue me for every penny I don't have. But I know you're out there and I'm guessing I'll hear the screams.

So what's my problem with fluoridation? For pretty much of my (longish) career I had no problem with it at all. I had an uncle who was a dentist in a midwestern city who fought against great odds to get the water fluoridated. He was a hero to many right thinking progressive people and took a lot of crap from some other Right Thinking Reactionaries. Those were the fifties when anti-communism was a real force and lovely folks like the John Birch Society were convinced fluoridation was a communist plot (it poisoned the "decision centers" in the brain so we couldn't resist the highly nuanced and persuasive prose of the Comintern). Then a few years ago one of my graduate students was asked by a friend of his to help construct toxicology arguments against fluoridating the water of a local community. He told me his first response to his friend was, "What, are you some kind of nut?" And then he said to himself, "Hey, wait a minute, I don't know anything about fluoride." So we decided to have a semester-long seminar series on the subject. What we learned was interesting.

Before I go on with this I'll tell you in advance there was no smoking gun about cancer or brain damage or some of the other things (like Alzheimer's) you hear talked about in regard to fluoride. There are some open questions involving fractures in the elderly and certainly there is some risk of cosmetic effects on teeth (little white flecks, mostly), even at levels that meet the standard. There are indeed a lot of interesting open toxicology issues related to fluoride, but that's not too different than many things, from the ingredients of over-the-counter medicines to cosmetics to water disinfection itself. Yes, there's a lot we don't know, but that's not unusual. If it is a risk benefit trade-off, I thought I understood the benefits pretty well.

I was surprised, however, to find that the mechanism whereby fluoride protects teeth (if it does) was poorly understood as was exactly who benefits. Is it just small children whose teeth are being formed or is there a "topical" effect that might protect everyone? Even more interesting is that dental caries have decreased also in many places where water is not fluoridated (e.g., Scandinavia, where fluoridation is essentially prohibited). Maybe something else is responsible for the decline in dental caries (e.g., nutritional status; Snickers Bars?).

Anyway, let's give it to them and say fluoride really does decrease dental caries. And I'm guessing it probably does to some extent. That's good, if true. And that if there are adverse effects, they are rare and not too serious. That would be good, too. But here's the rub (and it's an issue raised by the anti-fluoride people and it seems to me a real question). Is using the public water supply the right way to deliver a medication to the public? And if so, where should we stop. Wouldn't we get an even bigger benefit if we put tamoxifen (for breast cancer) or statins (for heart disease) in the water supply?

Maybe we should do it for fluoride. So what makes it different than statins? I think the water disinfection stuff is much clearer, but I'm still puzzled by the principle here. What is it? If this is cost benefit, doesn't breast cancer or heart disease win out easily over tooth decay? And if not, is it just the amount of money involved? (Where is George Bernard Shaw when we need him?)

If you have thoughts, weigh in. But please don't regale everyone with pro and con fluoride arguments. This is a question about an underlying public health principle. Which is...What, exactly?