Researchers from a top university have published a study indicating that water fluoridation could be causing Attention Deficit Hyperactivity Disorder (ADHD) in children and adults.
It was published in the peer-reviewed journal Environmental Health and examined rates of fluoridation beginning in 1992.
“States in which a greater proportion of people received artificially-fluoridated water in 1992 tended to have a greater proportion of children and adolescents who received ADHD diagnoses [in later years], after controlling for socioeconomic status,” one of the study’s authors, Ashley J. Malin of Toronto’s York University, told Newsweek.
Malin and her colleague, Christine Till, compared rates of fluoridation to the numbers of children diagnosed with ADHD.
The results are plausible, and indeed meaningful,” Harvard University Philippe Grandjean, an epidemiologist, said of the study. Grandjean said he has reviewed 27 studies that demonstrate a link between fluoridation and mental health problems. He told Newsweek that the studies should make authorities “reconsider the need to add fluoride to drinking water at current levels.”
American University researcher and risk assessment expert William Hirzy said the study’s results are significant.
“The numbers of extra cases associated with a one percent increase in the 1992 artificial fluoridation [figures] are huge,” Hirzy said. “In short, it clearly shows that as artificial water fluoridation increases, so does the incidence of ADHD.”
What the Study Found
The study used data collected in 2003, 2007 and 2011 as part of the National Survey of Children’s Health, and state water fluoridation records between 1992 and 2008.
Since 1992 the percentage of the US population that drinks fluoridated water increased from 56 percent to 67 percent. During the same period, the number of ADHD diagnoses in the United States increased from 7 percent to 11 percent.
States with high levels of fluoridation like Iowa and Delaware had higher levels of ADHD diagnoses. Around 14 percent or one in eight of the children between the ages of four and 17 in Iowa and Delaware were diagnosed with ADHD.
The study found that for each 1 percent “increase in artificial fluoridation” there were between 67,000 and 131,000 “additional ADHD diagnoses from 2003 to 2011.”
“Parents reported higher rates of medically-diagnosed ADHD in their children in states in which a greater proportion of people receive fluoridated water from public water supplies,” the study said. “The relationship between fluoride exposure and ADHD warrants future study.”
Harvard Professor: Fluoride is a Neurotoxin
Fluoride could cause ADHD and other mental problems because it is a neurotoxin that can damage the brain, Grandjean told Newsweek. Grandjean co-authored a study, “Neurobehavioral effects of developmental toxicity” that made the case against fluoride. That study – published in The Lancet — concluded that the world is suffering from a “pandemic of developmental neurotoxicity.”
“Industrial chemicals that injure the developing brain are among the known causes for this rise in prevalence,” the authors wrote. “… Untested chemicals should not be presumed to be safe to brain development, and chemicals in existing use and all new chemicals must therefore be tested for developmental neurotoxicity.”
The two made those conclusions after reviewing 27 studies of fluoride’s effect on the development of the brain.
The IQs of children born in areas with high levels of fluoride were seven points lower than kids from areas with low fluoride, Grandjean told Newsweek.