Overview
- Researchers reported Monday in the Proceedings of the National Academy of Sciences that community water fluoridation during childhood showed no link to lower IQ or later-life cognition.
- The team analyzed 10,317 people from the Wisconsin Longitudinal Study, using IQ scores at age 16 and cognitive tests at ages 53, 64, 72, and 80.
- Exposure was estimated from historical municipal fluoridation records and home addresses, not from urine or blood tests, and the data do not capture prenatal or infancy exposure.
- Many studies that tied fluoride to lower IQ looked at far higher levels in countries such as China and India, while U.S. systems aim for about 0.7 mg/L with a legal cap of 4.0 mg/L.
- The findings land as Utah and Florida ban fluoridation and other states consider limits, a policy turn dentists say could boost cavities as seen after cutbacks in places like Juneau and Calgary.