From the Guidelines
There is no compelling evidence that community water fluoridation at recommended levels is harmful to general health, and the benefits of reducing tooth decay outweigh potential risks. While some research has raised questions about potential concerns, major health organizations worldwide continue to support water fluoridation as a safe and effective public health measure for preventing tooth decay 1. Some studies have suggested possible associations between high fluoride exposure and issues like dental fluorosis (cosmetic mottling of teeth), which occurs primarily with excessive fluoride intake, and limited evidence has examined potential effects on neurodevelopment at higher exposure levels 1. However, these studies often have methodological limitations or examine fluoride levels significantly higher than those used in community water fluoridation programs.
The benefits of water fluoridation in reducing tooth decay, particularly among vulnerable populations, are well-documented and continue to outweigh potential risks according to public health authorities 1. Key points to consider include:
- The optimal concentration of fluoride in community drinking water to maximize caries prevention and limit enamel fluorosis ranges from 0.7 ppm to 1.2 ppm depending on the average maximum daily air temperature of the area 1.
- The U.S. Environmental Protection Agency (EPA) sets a maximum allowable limit for fluoride in community drinking water at 4 ppm and a secondary limit at 2 ppm 1.
- Current federal fluoridation guidelines state that community drinking water should contain 0.7--1.2 ppm fluoride, depending on the average maximum daily air temperature of the area 1.
If you're concerned about fluoride intake, you can use alternatives like non-fluoridated bottled water, but completely avoiding fluoride isn't necessary or recommended for most people from a health perspective. It's essential to weigh the potential risks and benefits and consider the scientific consensus that community water fluoridation is a safe and effective public health measure.
From the Research
Adverse Health Effects of Community Water Fluoridation
- Dental fluorosis is a known adverse health effect of community water fluoridation, with studies indicating that the severity of fluorosis is directly related to the concentration of fluoride in drinking water 2, 3.
- The risk of dental fluorosis increases with higher concentrations of fluoride in drinking water, with a suitable trade-off between caries and fluorosis appearing to occur around 0.7 ppm F 3.
- Fluoride intake above optimal levels can lead to dental fluorosis, which causes hypo-mineralisation of the tooth 4.
- Some studies have found that the severity of fluorosis is directly proportional to caries, while others have shown opposite results 4.
- High levels of fluoride in drinking water have been associated with an increased risk of skeletal fluorosis, bone fractures, and skeletal maturity, although the evidence for these effects is of very low certainty 5.
Association with Dental Caries
- Community water fluoridation has been shown to be effective in preventing dental caries, with a significant reduction in caries experience observed in many countries 2, 5.
- The initiation of community water fluoridation may lead to a slightly greater reduction in dental caries, although the effect size is smaller than in pre-1975 studies 5.
- The association between water fluoridation and dental fluorosis has been found to be significant, with approximately 12% of participants having fluorosis of aesthetic concern and 40% having fluorosis of any level at a fluoride level of 0.7 ppm 5.
Other Adverse Effects
- There is limited evidence on the adverse effects of community water fluoridation, with very low-certainty evidence for effects such as skeletal fluorosis, bone fractures, and skeletal maturity 5.
- Some studies have found that high levels of fluoride in drinking water may be associated with an increased risk of certain health problems, although the evidence is not conclusive 6, 4.