Monday, January 10, 2011

Less Fluoride, Stronger Bones and Teeth

How much fluoride in drinking water does it take to produce strong bones and teeth?

No one really knows, but there is no question that the current U.S. recommendation, around 1,000 parts per billion, or 1 part per million, is too much. That proportion was really just a guess by scientists and the fluoride lobby when it was first put forward 50 years ago, and now that there has been time to study the question, there is a consensus among scientists that the proper level is lower than this — if indeed fluoridated water is effective at all for people who use fluoride toothpaste every day.

And that’s part of the problem. People get fluoride in many other ways besides drinking water. Toothpaste, mouthwash, and other dental care products contain fluoride. Most food contains fluoride. Most of the beverages you drink contain roughly the same levels of fluoride as the tap water they are made from. When fruits and vegetables are irrigated with fluoridated water, they too contain fluoride. Meat, milk, and eggs contain fluoride if they come from animals that drink fluoridated water. Even baked goods contain fluoride — when bread is baked, most of the water evaporates, but the fluoride stays behind. Scientists have tried to measure and estimate the amount of fluoride people get, but there are only guesses so far. It is safe to say, however, that most people get most of their fluoride from sources other than the water they drink.

But it’s not just a question of effectiveness, but also of safety. Safety should be the first consideration for a substance like fluoride that is a potent neurotoxin and a regulated industrial waste, too dangerous to be disposed of in an ordinary landfill. Excess lifetime fluoride intake leads eventually to broken bones, most notably, hip fractures in women over 70 years of age. As mentioned, fluoride is a neurotoxin that, in cases of acute exposure, interferes with brain activity, putting a person into a kind of stupor.

Fluoride is thought to be effective only for older children between the ages of about 7 and 14. It is not imagined to be helpful for adults whose teeth and bones are already fully formed, and it is considered more dangerous than useful in children under about the age of 6. This is enough of a concern that recently, authorities have been recommending that baby food and infant formula be prepared with water that does not contain fluoride if possible.

Despite the scientific consensus, U.S. authorities held stubbornly to the recommendation of around 1,000 parts per billion — until today. The new recommendation, after the review process that will follow, will be 700 parts per billion, a reduction of about a third. This change is likely to be widely adopted, with no one so far, not even the fluoride lobby, stepping forward to oppose it. A water supplier could add a larger amount only on their own authority, and at considerable expense.

I believe this is a step in the right direction. My hope is that the reduction of fluoride levels by about one third will reduce the fluoride-related illnesses by about one half. But more importantly, a movement away from the “1 ppm” level that fluoride advocates adhered to for generations, like a religion, will allow a proper public policy discussion of what the ideal fluoridation level should be. We know that 1,000 parts per billion is too much. The new recommendation of 700 parts per billion is probably still too much, scientists say, but if it is, we will be able to say so conclusively after a few years of experience with it. Then it may be time to take another step down.