10 consecutive National Institutes of Health-funded studies between 2017 and 2024 show fluoride significantly impacts brain development in young children.

#1. Bashash et al. (2017) – Fluoride & IQ

The first of the NIEHS-funded studies reported an increase in maternal urine fluoride of 1 mg/L associated with a drop in IQ of 5 to 6 points.

“In this study, higher prenatal fluoride exposure, in the general range of exposures reported for other general population samples of pregnant women and nonpregnant adults, was associated with lower scores on tests of cognitive function in the offspring at age 4 and 6–12 y.”

#2. Thomas et al. (2018) – Fluoride & IQ

Reported lower IQ in children between 1 to 3 years of age. Only the abstract has been published, which reported pregnant women’s fluoride exposure is linked to lower IQ in their children.

“Our findings add to our team’s recently published report on prenatal fluoride and cognition at ages 4 and 6–12 years by suggesting that higher in utero exposure to F has an adverse impact on offspring cognitive development that can be detected earlier, in the first three years of life.“

Published in: British Medical Journal (May 2018)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), U.S. Environmental Protection Agency (EPA)

#3. Bashash et al. (2018) – Fluoride & ADHD

The authors reported higher concentration of maternal urinary fluoride was associated with more Attention Deficit Hyperactivity Disorder (ADHD)-like symptoms in school-age children.

“Higher levels of fluoride exposure during pregnancy were associated with global measures of ADHD and more symptoms of inattention as measured by the CRS-R in the offspring.“

Published in: Environmental Health Perspectives (December 2018)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), U.S. Environmental Protection Agency (EPA)

#4. Green et al. (2019) – Fluoride & IQ

Reported lower IQ in children between 3-4 years of age. Women living in areas with fluoridated tap water compared with non-fluoridated water had significantly higher mean urinary fluoride concentrations.

“In this study, maternal exposure to higher levels of fluoride during pregnancy was associated with lower IQ scores in children aged 3 to 4 years. These findings indicate the possible need to reduce fluoride intake during pregnancy.”

Published in: JAMA Pediatrics (August 2019)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), Health Canada, Ontario Ministry of the Environment, Canadian Institutes for Health Research

#5. Till et al. (2020) – Fluoride & IQ

Reported lower IQ in children at 3–4 years of age. Consumption of formula reconstituted with fluoridated water can lead to excessive fluoride intake.

“Exposure to increasing levels of fluoride in tap water was associated with diminished non-verbal intellectual abilities; the effect was more pronounced among formula-fed children.”

Published in: Environment International (January 2020)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), Health Canada, Ontario Ministry of the Environment, Canadian Institutes for Health Research

#6. Cantoral et al. (2021) – Fluoride & IQ

Reported lower IQ in children at 24 months of age. Higher exposure to fluoride in pregnancy was associated with reduced cognitive outcome.

“Higher exposure to fluoride from food and beverage consumption in pregnancy was associated with reduced cognitive outcome, but not with language and motor outcome in male offspring over the first two years of life.”

Published in: NeuroToxicology (December 2021)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS)

#7. Adkins et al. (2022) – Fluoride & Behavior

Found increased internalizing behavior, especially somatization, in adolescents with higher fluoride exposures.

“This is the first study to link fluoride exposure and internalizing symptoms, specifically somatization. Somatization represents an interface of physical and psychological health. Continued follow-up will help shed light on the sex-specific relationship between fluoride and mental health and the role of somatization.”

Published in: Environmental Research (March 2022)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), National Center for Advancing Translational Sciences (NCATS)

#8. Goodman et al. (2022) – Fluoride & IQ

The first study to investigate prenatal fluoride exposure and maternal iodine status in relation to the child’s IQ in boys and girls aged 3 to 4. Boys are impacted more.

“Our findings indicate that the association between prenatal fluoride exposure and full-scale intelligence previously identified in this cohort [6] was exacerbated by low maternal iodine in pregnancy among boys. These results, which were found among mother-child pairs living in fluoridated and non-fluoridated communities in Canada, underscore the importance of sufficient iodine intake in pregnancy to minimize the neurotoxicity of fluoride in boys.”

Published in: Nutrients (July 2022)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), Health Canada, Ontario Ministry of the Environment, Canadian Institutes for Health Research

#9. Hall et al. (2023) – Fluoride & IQ

The first study to investigate the relationships between maternal fluoride exposure and thyroid function on children’s IQ. Testing of children at 3-4 years of age found that boys are impacted more.

“Fluoride in drinking water was associated with increased risk of hypothyroidism in pregnant women. Thyroid disruption may contribute to developmental neurotoxicity of fluoride.”

Published in: Science of the Total Environment (April 2023)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), Health Canada, Ontario Ministry of the Environment, Canadian Institutes for Health Research

#10. Malin et al. (2024) – Fluoride & Behavior

The first study in the United States to investigate the association between prenatal fluoride exposure in the United States and neurobehavioral outcomes in children.

“In this prospective cohort study of mother-child pairs in Los Angeles, California, prenatal fluoride exposure was associated with increased neurobehavioral problems. These findings suggest that there may be a need to establish recommendations for limiting fluoride exposure during the prenatal period.”

Published in: JAMA Network (May 2024)
Funded by: U.S. National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS), U.S. Environmental Protection Agency (EPA)