No, U.S. NIH did not 'declare fluoride in water reduces IQ of children'

What's the claim?

A viral Instagram reel features a screenshot of an X (formerly Twitter) post by Calley Means, co-founder of Truemed, an alternative preventive medical care company. In the post, Means claims that the government "put fluoride in our water and attacked anyone who questioned it."

The post, which has garnered over 26,000 likes, also claims that the National Institutes of Health (NIH), the primary agency of the U.S. government for biomedical and public health research, has declared that fluoride consumption "reduces the IQ of children" and is "hazardous to human health." Additionally, it alleges that the U.S. states are now removing fluoride from their water supply. 

An archive link to a similar post can be found here. 

 
A screenshot of the Instagram post shows the claim that the NIH has declared fluoridated water lowers the IQ of children. (Source: Instagram/Modified by Logically Facts)

Flouride, a mineral and the ionic form of fluorine, is known for its benefits in preventing tooth decay and strengthening human bones. The U.S. Centers for Disease Prevention notes that fluoride repairs and prevents damage to teeth caused by bacteria in the mouth by replacing the minerals lost from a tooth due to acid breakdown.

In the U.S., water fluoridation — adding fluoride to an area's water supply — was first done in 1945 in Grand Rapids, Michigan. As of 2020, 72.7 percent of Americans had access to fluoridated water. 

The NIH research that the claim refers to is from the 'National Toxicology Program (NTP) Monograph on the State of the Science Concerning Fluoride Exposure and Neurodevelopment and Cognition: A Systematic Review.' However, upon examining the paper, we found the claim is misleading. 

The paper actually found that higher fluoride exposure, such as drinking water with fluoride concentrations exceeding the World Health Organization guidelines of 1.5 mg/L of fluoride, is consistently associated with lower IQ in children. The standard fluoride level for community water fluoridation is 0.7 mg/L in the U.S.

What does the paper say?

The monograph was published by NTP, an inter-agency program run by the U.S. Department of Health and Human Services. It is a systematic literature review on fluoride consumption and its effects on brain development and cognition. The report specifies that it is designed to evaluate the effects of fluoride from several sources, including drinking water, prepared beverages, foods, and dental products, not just water. Elaborating on fluoridated drinking water, the review notes that drinking water with a fluoride content of 1.5mg/L or more is associated with lower IQ in children. 

In addition, the report states that there is insufficient data to show that a 0.7 mg/L fluoride level in the water, which is the current level for community water fluoridation, can have negative effects.  

"This Monograph and Addendum do not address whether the sole exposure to fluoride added to drinking water in some countries (i.e., fluoridation, at 0.7 mg/L in the United States and Canada) is associated with a measurable effect on IQ," the report adds.

Additionally, WHO has set the maximum limit for water fluoridation at 1.5 mg/L. Therefore, it is not considered dangerous if the water supply is artificially fluoridated, less than 1.5 mg/L.

What have experts said?

Christine Flowers, director of the office of communications at the National Institute of Environmental Health Sciences of NIH, where the NTP is also located, told Logically Facts, "The NTP monograph concluded, with moderate confidence, that higher levels of fluoride exposure, such as drinking water containing more than 1.5 milligrams of fluoride per liter, are associated with lower IQ in children."

"The determination about lower IQs in children was based primarily on epidemiology studies in non-U.S. countries such as Canada, China, India, Iran, Pakistan, and Mexico, where pregnant women, infants, and children received total fluoride exposure amounts higher than 1.5 mg fluoride/L of drinking water," she added.

Flowers explained that many substances like fluoride are "healthy and beneficial" when taken in small doses but may cause harm in higher doses. She also stressed that the U.S. Public Health Service's 0.7 mg/L recommendation for water fluoridation level is followed across the U.S. where it is practiced and added that "more research is needed to understand if there are health risks associated with low fluoride exposures. The NTP monograph did not assess the health benefits of fluoride".

The National Institute of Dental and Craniofacial Research (NIDCR) Deputy Director Jennifer Webster-Cyriaque said, "Although the NTP review noted a connection between high fluoride and lower IQ, it did not conclude that high levels of fluoride cause lower IQ scores. We need more studies to better understand potential risks and benefits of higher levels of fluoride."

Furthermore, the American Dental Association (ADA) said that it has "reviewed the monograph and continues to stand behind community water fluoridation," adding that it "does not provide any new or conclusive evidence that should necessitate any changes in current community water fluoridation practices for public health policy consideration."  

The ADA report also quoted Dr. Scott Tomar, a member of the National Fluoridation Advisory Committee and a professor and associate dean at the University of Illinois at Chicago College of Dentistry, as saying, "The bottom line is that the National Toxicology Program report and other recent systematic reviews indicate that the level of fluoride used in community water fluoridation is effective for preventing tooth decay and is not associated with any change in people’s IQ or neurological development."

The verdict

The claim is misleading as the NIH has not "declared" that fluoridated water reduces children's IQ and is hazardous to human health. Water fluoridated at recommended levels by the World Health Organization is considered safe to consume and beneficial for dental health.