While the study is only able to establish an association, not cause-and-effect, experts say the link deserves serious investigation.
“Clinicians in the United States should emphasize to patients this association and should test patients for underactive thyroid,” said Dr. Spyros Mezitis, an endocrinologist at Lenox Hill Hospital in New York City.
“Patients should probably be advised to drink less fluoridated water and consume less fluoridated products, including [fluoridated] toothpaste,” added Mezitis, who was not involved in the study.
But a representative of the American Dental Association took issue with the British report.
“Public health policy is built on a strong base of scientific evidence, not a single study,” said Dr. Edmond Hewlett, ADA spokesman and a professor at the UCLA School of Dentistry. “Currently, the best available scientific evidence indicates that optimally fluoridated water does not have an adverse effect on the thyroid gland or its function.”
The new study was led by Stephen Peckham of the University of Kent in Canterbury, England. They compared 2012 national data on levels of fluoride in drinking water to trends for hypothyroidism (underactive thyroid) as diagnosed by family physicians across England.
Source : Webmd.com