Check the Facts
Fluoridation:
What the Science Really Says
Community Water Fluoridation & Caries Prevention in Adults
Dr. Gary Slade of UNC School of Dentistry describes his study on the effects of fluoridation on dental caries in Australian adults and discusses implications for the U.S. population and cost-benefit calculations of community water fluoridation.
Recent Reviews
The authors conducted a large ecological study to evaluate the association of fluoride in drinking water with hypothyroidism in England. The units of analysis were general medical practices characterized by practice-level prevalence of hypothyroidism. These were assessed in relation to fluoride level in drinking water at the site of the medical practices. Mean and maximum concentration of fluoride in drinking water (mg/L) was provided by the Drinking Water Inspectorate. Hypothyroidism prevalence was obtained from the Quality of Outcomes data set. Covariates included in this study were practice-level IMD scores (a measure of social deprivation for a geographic area), proportion of the practice population ≥40 years of age and proportion that was female. The authors concluded that fluoride... Read More
An ecological design was used to examine if states with more widespread water fluoridation would have higher ADHD prevalence. State-based ADHD prevalence estimates (2003, 2007, 2011) and fluoridation prevalence (for years 1992, 2000, 2002, 2004, 2006, and 2008) were obtained from the Centers for Disease Control and Prevention website, and then statistical analyses were performed using these estimates. The authors concluded that there is an association between ADHD prevalence and fluoridation prevalence and hence the fluoridated water may be an environmental risk factor. However, some of the findings are not consistent with their hypothesis of interest and also, the internal validity of the study is highly questionable. The authors acknowledged that there was no previous research linking fl... Read More
The study found a possible association between fluorosis and IQ. But based on this study’s evidence, no causal relationship can be determined. Potential confounders such as environmental pollutants are not accounted for in the statistical analysis or discussion.
The purpose of this study was to assess whether fluoride levels in bone were associated with osteosarcoma. A case-control design was used to compare bone fluoride levels in 137 subjects with primary osteosarcoma (cases) with 51 controls that had other malignant bone tumors. The median age of cases was 17.6 years old. The median age of controls was 41.3 years old. The gender distribution also differed with 53 percent of cases being male compared to 71 percent of controls. A subset of 32 cases was matched with controls based on gender and age. The study did not demonstrate an association between fluoride levels in bone and osteosarcoma. This was true even after adjusting for age and gender in the statistical analysis in the unmatched cases and controls.
Overall, I can say that if this paper had been sent to me for review, it would not have been accepted for publication.