Being both a former dental professional and a public health student I flipped out just a bit when I first moved to Albuquerque and learned about water fluoridation in Albuquerque. Albuquerque doesn’t fluoridate their tap water. Shortly after learning this I went to Target and bought some nursery water that contained fluoride. To be honest, I never really used it, but I was still a bit paranoid.
Yesterday when I spoke with Dr. Lindsay Essenmacher I also asked her a question about water fluoridation. I was curious if she recommend parents give their children fluoridated water like I bought or otherwise expose their children’s teeth to extra fluoride in light of the lack of added fluoride in our tap water. Dr. Essenmacher said,
I think it’s important to note that even though Albuquerque doesn’t fluoridate the water anymore, our water still contains naturally occurring fluoride in the range of 0.4-0.5 ppm (optimal is 0.7 ppm). We also consume additional fluoride in the form of toothpaste, mouthwashes, and even certain food and beverages. However, I would recommend supplemental fluoride when (1) the child and immediate family members have a history of cavities and (2) the child drinks mainly bottled water or water from a purifier that removes fluoride. There is a risk of fluorosis if too much fluoride is ingested; therefore, fluoride supplementation must be prescribed judiciously.
Before we dive into water fluoridation, I’d like to back up and look at a more basic question: what causes tooth decay?
Tooth decay is one of the most prevalent chronic diseases of childhood. Tooth decay can occur when certain bacteria are present in the mouth and the mouth is exposed to sugar (in many forms, not just white table sugar). The Mayo Clinic has a good description of how cavities form, but basically the bacteria eat the sugars that we put in our mouth and then they produce an acid that attacks the enamel (the hard pearly white part) of our teeth. This acid causes what is known as de-mineralization (the dissolution of a tooth’s mineral content). This de-mineralization creates little holes in the tooth. The bacteria and acid can now move into the tooth, and the cavity grows.
This is all very interesting (or at least it is to me), but what does this have to do with water fluoridation?
Basically, fluoride is important because it is a mineral that helps re-mineralize enamel that has started to breakdown by de-mineralization. In this way, fluoride can help prevent tooth decay. In young children with teeth that are still developing, systemic (or ingested) fluoride also makes the teeth stronger than they would have been without the systemic fluoride.
Community water fluoridation has long been considered a huge public health achievement, and the CDC even named it as one of the top ten achievements in the last century.
In May of last year the U.S. Public Health Service updated the drinking water standards related to community water fluoridation. According the Public Health Service the optimal fluoride concentration is 0.7 miligrams/liter. After many studies and much thought, the U.S. Public Health Service concluded this was the best balance of protecting the population from tooth decay while still limiting the risk of fluorosis (a discoloration of the teeth that is primarily of cosmetic concern).
While further poking around the web I was surprised to find that a recent Cochrane Review found very little current evidence to either support community water fluoridation or to recommend stopping community fluoridation. This review found that water fluoridation was effective at significantly reducing levels of tooth decay among children, but that there were no noticeable differences in adults. This makes sense since as teeth are developing in early childhood, systemic fluoride, like that consumed through drinking water, helps create stronger teeth that are less prone to decay. However, as the review itself points out, most of the data for this study was conducted prior to 1975, and dental habits have changed since that time.
The authors of this review also found a significant association between water fluoridation levels and dental fluorosis. At a fluoridation level of 0.7 miligrams/liter they estimate that approximately 12% of the population will have some level of fluorosis. So, as so often is the case, I guess there’s no clear answer on the current benefits of water fluoridation.
As Dr. Essenmacher pointed out, our water here in Albuquerque does contain naturally occurring fluoride at levels that provide some dental benefits. But, what are your thoughts? Are you glad that Albuquerque doesn’t add fluoride to our water, or would you rather they did?