A top doctor has urged pregnant and lactating women not to drink tap water containing fluoride as the mineral could damage the fetus’ brain.
Dr. Michael Greger, author of the How Not To Die series, said that even parents who give their children formula should avoid mixing it with water treated with fluoride, which he called a “putative developmental neurotoxin.”
Speaking to DailyMail.com, he said: ‘Pregnant women, lactating women and women with babies who are fed water mixed with infant formula should try their best 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 that high levels of fluoride could cause children’s IQs to drop by as much as five points.
The map above shows the states that do and do not participate in the CDC’s My Water’s Fluoride Monitoring System
The above shows the most recent known levels of fluoride in U.S. county water systems
Your browser does not support iframes.
Fluoride is a naturally occurring mineral found in water, soil and various foods. It has been added to public water systems since 1945 for its protective properties, with the goal of reducing tooth decay and promoting overall good oral health.
The issue surrounding fluoride in tap water is controversial because its introduction is considered one of the greatest public health achievements due to its effectiveness in reducing tooth decay in children.
About 80 years ago, scientists discovered that people whose water supplies naturally contained more fluoride also had fewer cavities. They found that it replaces minerals in teeth lost due to decay and wear.
This sparked an effort to get more Americans to use fluoride, found in toothpaste, and to add the mineral to the national drinking water supply.
More than 200 million Americans drink water containing fluoride, or 75 percent of the population, more than any other country in the world.
And the CDC estimates it could reduce cavities by 25 percent and save about $6.5 billion in dental costs annually.
Most tap water in the US contains fluoride at about 0.7 milligrams per liter (mg/L), which is considered the “optimal” level.
But this figure is almost double what experts and studies have established as the safe limit for pregnant women and infants: 0.4 mg/l.
The Environmental Protection Agency (EPA) says fluoride levels in water should not exceed 4 mg/L, warning that higher levels increase the risk of skeletal fluorosis or skeletal deformities.
The World Health Organization has set a limit of 1.5 mg/l.
An EPA spokesperson said the agency is investigating how fluoride is regulated following a California court ruling this week that found fluoride posed a “hazard” to children’s health and said the EPA must investigate.
In his ruling, Judge Edward Chen said: ‘The scientific literature in the case provides a high degree of certainty that a hazard is present; fluoride is associated with lowered 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 such as Germany, which does not fluoridate its tap water.
But other countries, such as Britain, are even going 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 to reduce the prevalence of tooth decay and improve dental health across the country.
Dr. Michael Greger warned pregnant women not to drink water containing fluoride
Filter pitchers 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 that when someone drinks water containing fluoride, the chemical enters the bloodstream and can then travel to the brain.
Hypotheses suggest that fluoride could disrupt the brain during development, leading to children having lower IQs.
It is also possible that it crosses the placental barrier and reaches a fetus, where it can also disrupt brain development.
Additionally, experts say it is possible for the fluoride to enter breast milk and be transmitted to a baby.
Dr. Greger said it’s also possible that fluoride affects brain health in adults, but more studies are needed to determine this.
A study published this year in JAMA network opened found that fluoride exposure during pregnancy was associated with increased behavioral problems in children.
The paper, which followed 229 pregnant women and their children, found that a 0.68 mg/l increase in urine fluoride levels during pregnancy was associated with babies being almost twice as likely to have behavioral problems , such as internalizing or externalizing problems.
And a report from the National Toxicology Program (NTP) warned of lower IQ in children exposed to high levels of fluoride, based on 19 high-quality studies.
Far more counties in the US are fluoridating their water than any other country in the world, according to National Population Review data for the year 2024
Dr. Greger told DailyMail.com: ‘This is really about protecting pregnant mothers, breastfeeding mothers and babies who are fed water mixed with infant formula.
‘Ideally, we would stop fluoridation to protect these vulnerable communities.
“They should just drink that purified water during pregnancy, breastfeeding and then when mixing formula, to get the best of both worlds until we (the researchers) figure out what’s going on.”
Dr. Greger said he had previously supported the consensus on adding fluoride to drinking water — and even considered those who argued otherwise as “crazy.”
But while researching his latest book, published in 2020, he read some research that convinced him that 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 had a filter installed at home, but this is to remove carbon and ‘improve the taste of the water’.
But he said that when he meets a pregnant woman or a woman with a very young child, he urges them not to drink tap water that contains fluoride.
The American Dental Association is leading calls to proclaim fluoride as safe and is pushing for it to be added to local water supplies.
Advocacy groups such as the Fluoride Action Network are at the other end of the scale, arguing that claims that fluoride is safe are exaggerated.