
United States Secretary of Health and Human Services Commissioner Robert F. Kennedy Jr. has made headlines with his stance on water fluoridation (the process of adding fluoride to public water supplies to help prevent tooth decay). His proposal to remove fluoride from public drinking water systems is based upon his research that fluoride is a “dangerous neurotoxin,” with links to various health issues such as IQ issues among children, arthritis, bone fractures, bone cancer, neurodevelopmental disorders, and thyroid disease.
It represents a significant challenge to a public health practice that has been in place for over 75 years in the United States.
Kennedy’s Position on Fluoride
Kennedy has been vocal about his opposition to water fluoridation, calling it a form of “mass medication” that violates individual choice. He argues that adding fluoride to public water supplies forces people to consume a substance they may not want, regardless of their personal health decisions or beliefs.
Kennedy’s concerns center around several key points:
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- Potential health risks associated with fluoride consumption.
- Questions about the ethics of mass medication through water supplies.
- Arguments that fluoride’s benefits can be achieved through other means, such as toothpaste and dental treatments.
Kennedy has pointed explicitly to studies suggesting potential links between fluoride exposure and children’s IQ:
A note about liquid measurements and their association with fluoride in drinking water:
A U.S. fluoridation level of 0.7 mg/L, which is the amount of fluoride in drinking water, equals about 0.021 milligrams of fluoride per fluid ounce of water.
Putting it another way, 0.00000073 ounces = about 7.3 ten-millionths of an ounce. This is an extremely small amount. For reference, a single grain of table salt weighs about 0.1 mg, so 0.0207 mg is about one-fifth the weight of a grain of salt.
Now that you understand the amount of fluoride in water, let’s see how the comparisons work in these studies below.
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- JAMA Pediatrics Meta-Analysis (2025): This review analyzed 64 studies and found the more fluoride children were exposed to, the lower their IQ scores tended to be; however, the authors noted that many of the studies had a high risk of bias, and the analysis was not designed to assess the public health implications of water fluoridation in the U.S.
- National Toxicology Program (NTP) Review (2024): The NTP study concluded with moderate confidence that higher levels of fluoride exposure (above 1.5 mg/L) are associated with lower IQ in children. However, there was insufficient data to determine effects at the standard U.S. fluoridation level of 0.7 mg/L.
- Harvard Meta-Analysis (2012): Researchers from the Harvard School of Public Health and China Medical University combined 27 studies and found strong indications that fluoride may adversely affect cognitive development in children. They emphasized the need for further research on the impact of fluoride on the developing brain.
- CDC & ADA Acknowledgement: Fluorosis is the most widely accepted side effect, and is the reason the U.S. lowered the recommended fluoride level in water to 0.7 mg/L in 2015.
Additional studies reveal other health issues:
Bone Health (Fractures, Arthritis, Cancer)
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- A Study on Bone Fractures found a link between high fluoride exposure and increased risk of bone fractures, especially in elderly populations.
- Osteosarcoma (Bone Cancer) Risk: Some early studies (1990s–2000s) suggested a potential link between fluoride and osteosarcoma in young males, but later reviews, including from the National Research Council (2006) and Harvard, concluded that the evidence is inconclusive.
Neurodevelopmental Disorders
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- In addition to the IQ studies, some researchers (e.g. Grandjean & Landrigan, 2014, The Lancet Neurology) include fluoride on a list of developmental neurotoxicants (chemicals or substances that can damage the developing nervous system, particularly during critical periods of brain development in fetuses, infants, and young children.)
Thyroid Disease
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- A UK Study (Peckham et al., 2015, Journal of Epidemiology & Community Health) found that areas with higher fluoride levels had higher rates of an underactive thyroid.
Summary
While most health agencies (CDC, ADA, WHO) still support fluoridation at 0.7 mg/L, Kennedy and others argue for a more precautionary approach based on:
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- Emerging research (often on high-exposure cases)
- Concerns about vulnerable populations.
- Advocacy for individual choice over public mandates.
What’s Next?
Whether we’ll see changes to fluoride in our drinking water will depend on several factors, including the influence Kennedy can have on local policies and how public health groups and water companies respond.
This entire discussion highlights the ongoing conversation between established public health practices and people’s increasing questions about government health programs. As we continue to discuss this, communities around the country may find themselves examining the research, considering what works best for their area, and deciding on a course of action regarding fluoride in their local water supply.
Whatever we decide could shape how we approach dental health, public health practices, and how we balance personal choice with what’s good for the whole community going forward