A top doctor has urged pregnant and breastfeeding women to avoid drinking tap water that contains fluoride because the mineral could damage fetuses’ brains.
Dr Michael Greger, author of the How Not To Die series, said even parents who feed their children formula should avoid mixing it with water treated with fluoride, which he called a ‘presumed developmental neurotoxin.’
Speaking to DailyMail.com, he said: ‘Pregnant and breastfeeding women and those with infants who are getting water mixed with infant formula should try to go out of their way to use unfluoridated water.’
His comments come days after a federal judge warned that fluoride, added to water systems to strengthen teeth and reduce cavities, posed an ‘unreasonable risk’ to children’s brains.
And just a month after a 320-page government report found fluoride in high concentrations could lead to children’s IQ dropping by up to five points.
The above map shows the states participating, and not participating, in the CDC’s My Water’s Fluoride monitoring system
The above shows the most recently known levels of fluoride in US county water systems
Fluoride is a naturally occurring mineral found in water, soil and various foods. It’s been added to public water systems since 1945 for its protective qualities, with the goal of reducing tooth decay and promoting generally good oral health.
The issue around fluoride in tap water is controversial because its introduction is considered to be one of the greatest public health achievements due to its effectiveness in reducing tooth decay in children.
About 80 years ago, scientists discovered people whose water supplies naturally had more fluoride in it also had fewer cavities. They determined it was replacing minerals in teeth that were lost to decay and wear and tear.
This triggered a push to get more Americans to use fluoride, which is in toothpaste, and to have the mineral added to national drinking water supplies.
More than 200million Americans drink water that contains fluoride, or 75 percent of the population, more than in any other country in the world.
And the CDC estimates it could be reducing cavities by 25 percent and saving about $6.5billion every year in dental costs.
Most tap water in the US contains fluoride at a level of about 0.7 milligrams per liter (mg/L), which is considered the ‘optimal’ level.
But this figure is nearly double what experts and studies have determined to be the safe limit for pregnant women and infants – 0.4 mg/L
The Environmental Protection Agency (EPA) says fluoride levels should not be above 4 mg/L in water, warning any higher levels raise the risk of skeletal fluorosis, or deformities in the skeleton.
The World Health Organization has set a limit of 1.5 mg/L.
A spokesperson for the EPA said the agency was reviewing how fluoride is regulated following a ruling in a California court this week that found fluoride posed a ‘hazard’ to children’s health and said the EPA should conduct an investigation.
In his ruling, Judge Edward Chen said: ‘The scientific literature in the record provides a high level of certainty that a hazard is present; fluoride is associated with reduced IQ.’
There has been controversy over fluoride in the water supply for years, with hundreds of communities voting against its use (Above is a campaign sign from Kennebunk, Maine)
In an interview with this website, Dr Greger urged the US to follow the example of European countries like Germany, which does not fluoridate its tap water.
But other nations, like the UK, are actually pushing ahead with plans to add more fluoride to their tap water, making it available to millions more Britons.
British officials have said the plan should be expanded in order to reduce the prevalence of tooth decay and to improve dental health across the country.
Dr Michael Greger warned pregnant women not to drink water containing fluoride
Filtering jugs and filter systems that claim to filter out fluoride are available online for up to $250. Manufacturers say they are up to 97 percent effective.
Experts say when someone drinks water that contains fluoride, the chemical enters the bloodstream and can then travel to the brain.
Hypotheses suggest the fluoride could then interfere with the brain during development leading to children having a lower IQ.
It is also possible for it to cross the placental barrier and reach a fetus, where it could also disrupt brain development.
Additionally, experts say it is possible for the fluoride to enter breastmilk and be transferred to an infant.
Dr Greger said it was also possible that fluoride was impacting the brain health of adults, but that more studies were needed to determine this.
A study published this year in JAMA Network Open found that fluoride exposure during pregnancy was linked to increased behavioral problems in children.
The paper, which tracked 229 pregnant women and their children, found a 0.68 mg/L increase in urinary fluoride concentrations during pregnancy was associated with infants being nearly twice as likely to have behavioral issues, such as internalizing or externalizing problems.
And a report from the National Toxicology Program (NTP) warned of lower IQ among children exposed to high levels of fluoride based on 19 high-quality studies.
Far more counties in the US fluorinate their water than in any other country in the world, data from the National Population Review for the year 2024 reveals
Dr Greger told DailyMail.com: ‘This is really about protecting pregnant mothers, breastfeeding mothers and infants who are getting water mixed with infant formula.
‘Ideally, we would stop fluoridation to protect these vulnerable communities.
‘They should just be drinking that purified water during pregnancy, breastfeeding, and then when mixing formula, to get the best of both world’s until we [the researchers] have figured out what’s going on.’
Dr Greger said he had previously backed the consensus around fluoride being added to drinking water — and even considered those arguing otherwise as ‘crazy’.
But while researching his latest book, published in 2020, he read a number of studies that convinced him fluoridation may not be as safe as first thought.
Dr Greger, who lives in Virginia, still drinks his local tap water which contains fluoride. He has a filter installed at home, but this is to remove carbon to ‘improve the water’s taste’.
But he said whenever he meets a pregnant woman or a woman with a very young child, he urges them to avoid drinking tap water that contains fluoride.
The American Dental Association has been at the forefront of calls proclaiming fluoride as safe and pushing for it to be added to local water supplies.
Advocacy groups like the Fluoride Action Network have been at the other end of the scale, arguing that claims fluoride is safe have been exaggerated.
