Could fluoride be bad for your baby during pregnancy?

Could fluoride be bad for your baby during pregnancy?

Fluoride exposure from drinking water during pregnancy could be making children less intelligent, a new Canadian study argues.

Expectant moms with higher levels of fluoride in their urine tended to have kids with lower average IQs, based on a study of 601 mother-child pairs from six cities in Canada.

On average, a 1 milligram-per-liter increase in maternal urinary fluoride was associated with a 4.5-point lower IQ score in boys by the time they reached ages 3 to 4, researchers report.

"Four and a half IQ points is of substantial societal and economic concern," said senior researcher Christine Till, an associate professor of psychology at York University in Toronto. "We're talking a magnitude that's comparable to what we're talking about when we talk about lead exposure.

"You would have millions of more children falling into the range of intellectual disability with IQ scores of less than 70, and that many fewer kids in the gifted range," Till concluded.

However, the researchers only found an association, due to the observational nature of the study. It was published Aug. 19 in JAMA Pediatrics.

Debate over fluoridation has simmered since cities began adding the mineral to public supplies in the 1950s, Till said.

Two out of every three U.S. residents now live in an area with fluoridated water, compared with 38% of Canadians and 3% of Europeans, the researchers said in background notes.

Despite these findings, more studies with similar results will be needed to prompt a tough reconsideration of fluoride's safety, said pediatric neuropsychologist David Bellinger, a professor of neurology at Harvard Medical School and a professor of environmental health at the Harvard T.H. Chan School of Public Health.

"In my view, a strong case for a hypothesis is present when multiple studies conducted independently produce consistent results. I don't think we are there yet in terms of fluoride neurotoxicity, but the results of this study move the needle in that direction," said Bellinger, who wrote an editorial accompanying the report.

"When it comes to epidemiology, it is unwise to place too much emphasis on the results of any one study," Bellinger concluded, although he noted that Till and her colleagues produced a "very good environmental epidemiology study."

The American Dental Association released a statement saying it "remains committed to fluoridation of public water supplies as the single most effective public health measure to help prevent tooth decay.

"Throughout more than 70 years of research and practical experience, the overwhelming weight of credible scientific evidence has consistently indicated that fluoridation of community water supplies is safe," the ADA said. "The evidence-based research shows the recommended concentrations of fluoride (0.7 mg/L) used in community water fluoridation is beneficial and safe for the public.

"We welcome this and further scientific study of the issue to see if the findings can be replicated with methods that demonstrate more conclusive evidence," the ADA said.

For the Canadian study, the researchers gathered from during each trimester and tested their fluoride levels. They also tracked the women's potential exposure to fluoride by asking them to fill out a questionnaire regarding how much water, tea, coffee and other water-based beverages they drank.

Their children's IQ scores were then assessed once they reached ages 3 to 4, and those scores were compared against the fluoride in mom's urine during pregnancy.

Fluoride crosses the placenta, and lab studies have shown that the mineral accumulates in brain regions involved in memory and learning, researchers said in background notes. Fluoride also has been shown to alter proteins and neurotransmitters in the central nervous system.

The researchers found that urinary fluoride levels during pregnancy were associated with lower IQ scores in boys, but no statistically significant association was found in girls.

"We found that fluoride exposure in pregnancy was associated with lower IQ scores in these preschool-age children," Till said, though the study could not prove that fluoride exposure actually caused IQ levels to drop.

The study follows on the heels of a 2017 study in Mexico City that associated maternal urinary fluoride levels with a 6.3-point decrease in IQ levels among boys and girls, Till said.

"I definitely think emerging research is making the science evolve," Till said.

Pregnant women should consider reducing their exposure to fluoride, Till said. That might include avoiding public water sources that are fluoridated, since those account for 70% of fluoride exposure in adults.

"There's absolutely no benefit of fluoride to a fetus or a baby without teeth," Till said. "You're not doing any harm to your baby by reducing your intake. You can reduce it and your baby will be fine."

Explore further

Fluoride levels in pregnant women in Canada show drinking water is primary source of exposure

More information: The American Dental Association has more about fluoride.
Journal information: JAMA Pediatrics

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User comments

Aug 19, 2019
Remember, the Nazis fluoridated water first, the ADA is citing fascist "science." The argument that this is about dental hygiene never made sense, and the scientific basis for it was never rigorous. Calcium fluoride such as naturally-occurring in the Rocky Mountains may be harmless, but dumping sodium hexafluoride toxic waste from the aluminium industry into drinking water supplies certainly is not.

Aug 19, 2019
Remember, the Nazis fluoridated water first
"Dean and his colleagues conducted a controlled experiment by fluoridating the water in Grand Rapids, Michigan, starting 25 January 1945. The results, published in 1950, showed significant reduction of cavities.... Fluoridation became an official policy of the U.S. Public Health Service by 1951, and by 1960 water fluoridation had become widely used in the U.S., reaching about 50 million people."

"Federal Republic of Germany (1952–1971)"

"Later conspiracy theories... "Both the Germans and the Russians added sodium fluoride to the drinking water of prisoners of war to make them stupid and docile." These statements have been dismissed by reputable Holocaust historians as untrue, but they are regularly repeated to the present day in conspiracy publications and websites."

-IOW youre full of shit.

Aug 19, 2019
The article is:


Association Between Maternal Fluoride Exposure During Pregnancy and IQ Scores in Offspring in Canada
Rivka Green MA; Bruce Lanphear, MD; Richard Hornung, PhD; et al

Also of interest is the contribution of tea to fluoride consumption, which mentions babies and children being given tea, containing caffeine and fluoride. It cites other research which shows that the topical application of fluoride to the tooth surface itself is what helps with preventing cavities, and that actually ingesting fluoride is bad for health in many respects.


Aug 20, 2019
Otto, perhaps don't get too cross with 1st poster?
It is a failure of science, the process, that even reasonable contrary opinions - like fluoridation not being all good- get thrown in the same bucket as full-on conspiracy theory. The process does not allow dissent without an extraordinary burden of proof. Then something like this paper comes along, exposing the fallacies at the heart of the decision-making process:
Fluoride is of no benefit in pregnancy and quite likely to disrupt it in subtle ways (like IQ) that take years to manifest.
There were no real "control" groups, it was rolled-out across the world.
The sources of Fluoride were nothing like reagent quality, so many contaminants were essentially open risks.
There was no realistic option for opt-out.
All of these points are from genuine scientific prerequisites and should not be dismissed, awaiting proof-of-harm.

Aug 21, 2019
Otto, perhaps don't get too cross with 1st poster?
Usually I'm polite with nobs unless they fail to research before they post.

You've made many assertions without any refs or links. I bet only a few searches would determine that you are full of shit as well. For instance
was rolled-out across the world
"As of 2012, about 435 million people worldwide received water fluoridated at the recommended level (i.e., about 5.4% of the global population). About 214 million of them living in the United States."

-So at least in one case you are only a little full of shit. Irrespective of this suspect statement:
All of these points are from genuine scientific prerequisites
-which, from an anonymous source, is always cause for doubt.

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