There's been a lot of talk recently about the presence of fluoride in the water supplies of cities across the United States and possible health risks associated with the chemical's consumption. Now, a new study is adding to the scientific literature debunking one popular claim.
The latest research, published Dec. 18 in the Journal of Dental Research, found that people aged 16 to 26 years old who have been consistently drinking fluoridated since childhood had an average IQ score that was 1.07 points higher than those with no exposure. In addition, people with dental fluorosis, used in determining excessive fluoride intake in early childhood, had IQ scores 0.28 higher on average than those without it.
"There have been claims water fluoridation can negatively affect children's neurodevelopment, but these results provide consistent evidence this is not the case," study lead author Loc Do said in a statement.
"Dental decay or cavities are the most common chronic childhood disease worldwide, which can be quite painful, and teeth often have to be removed. Fluoridation is very effective in preventing these issues, and this research provides reassurance that it is safe to be expanded into more communities," study co-author Diep Ha added.
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It should be noted, however, that water fluoridation is probably only considered safe up to a certain concentration. A U.S. government report released back in August found that consuming fluoride at twice the recommended limit (0.7 milligrams per liter, per the U.S. Department of Health and Human Services) was associated with lower IQ in children. That figure, however, remains in place.
"It is important to note that there were insufficient data to determine if the low fluoride level of 0.7 milligrams per liter currently recommended for U.S. community water supplies has a negative effect on children’s IQ," the report read. Adults, meanwhile, appear to be in the clear, as the National Toxicology Program "found no evidence that fluoride exposure had adverse effects on adult cognition."
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Still, if you're concerned (or just want better-tasting tap water), consider investing in a home water filter.