A New Court Ruling Is Raising Concerns About Too Much Fluoride in Drinking Water. Here’s What You Need to Know

Fluoride has come under the microscope after a federal judge ruled that the U.S. Environmental Protection Agency (EPA) must add more regulations around the mineral’s presence in drinking water.

U.S. District Judge Edward Chen said mounting evidence suggests the amount of fluoride usually added to water could potentially lead to lower IQs in children, the Associated Press reported yesterday. Chen ruled that the EPA must take steps to lower this risk to children’s development, although he didn’t outline exactly what those steps should be.

Fluoride has been added to drinking water since 1945 in an effort to promote tooth health in children. In fact, research has found that adding fluoride to water lowers the amount of tooth decay in young kids by 35 percent. The Centers for Disease Control and Prevention (CDC) even lists fluoridation of water (the practice of adding fluoride to water) as one of the greatest public health achievements of the 20th century.

But other research has questioned the safety of this practice and linked it to neurodevelopmental issues in children. Here’s what you need to know.

Wait, why is fluoride in our water?

Fluoride is a mineral and element that’s naturally found in rivers, lakes, and oceans, as well as in some foods and drinks, per the American Dental Association (ADA). The element helps to strengthen teeth. The ADA calls fluoride “nature’s cavity fighter,” pointing out that it’s usually added to toothpaste and other dental products to help protect teeth against cavities.

“Fluorinating water is a cost-effective way to reduce cavities and dental decay,” Jamie Alan, PhD, an associate professor of pharmacology and toxicology at Michigan State University, tells Well+Good.

“It’s a dental safety net,” says Kenneth Markowitz, DDS, an associate professor of oral biology at the Rutgers University School of Dental Medicine.

However, he notes that much of the research into the benefit of adding fluoride to drinking water was done decades ago. “In this day and age, it gets a little harder to see the benefit because people’s dental health in general has improved since the 1940s,” he says.

What are the major concerns about fluoride?

A lot of the concern is tied to a government report released last month that found that fluoride in drinking water at twice the recommended limit is linked with lower IQ in children. The report determined with “moderate confidence” that a link exists between higher levels of fluoride and lower IQs in kids. The EPA, meanwhile, has stressed that it’s not clear what effect, if any, lower levels of fluoride might have on children’s intellectual development.

Federal health officials currently recommend a fluoridation level of 0.7 milligrams per liter of water¹. But the exact level at which fluoride may affect a child’s IQ has not yet been determined.

Still, “fluoride is toxic to brain development at elevated levels,” Philippe Grandjean, MD, professor of Clinical Pharmacology, Pharmacy, and Environmental Medicine at The University of Rhode Island, tells Well+Good.

Indeed, in 2014, The Lancet² medical journal designated fluoride as a neurotoxin, leading federal health officials to advise local governments to lower the amount of fluoride in the U.S. water supply (the upper limit used to be 1.2 milligrams per liter).

Too much fluoride in water can also lead to a condition known as dental fluorosis, which causes white or brown spots on teeth, along with other health complications like bone weakening and damage, arthritis, osteoporosis, muscular damage, fatigue, and joint-related problems, Alan says.

“Certainly, fluoride is a potentially toxic substance,” Markowitz says. “It’s hard for people to get their minds around [the fact] that small amounts are beneficial.”

What to do if you’re worried about fluoride in your water

If this news about fluoride has you concerned, there are a few things you can do. The CDC encourages people to contact their local water provider for information about fluoride levels in community water systems.

“Typically, your health department or city government will test the water for you for a small fee,” Alan says, adding: “If you are on well water or spring water, your water may or may not contain fluoride.”

Keep in mind that water systems are required to tell you if your fluoride water levels are higher than 2.0 mg/L, per the CDC.

Additionally, “you could consider using a filter that removes fluoride from water used for drinking or cooking,” Alan says. Bottled water may also be a solution, “although some brands may contain fluoride or other unwanted chemicals,” Dr. Grandjean cautions.

“Because fluoride is not absorbed through the skin, you do not need to filter [water used] for cleaning and bathing,” Alan says.

But it’s also important to put all of this into perspective. It’s true that too much fluoride is not good for kids, but we don’t know for sure that the amount typically added to water is above the safe threshold. Yesterday’s ruling is more about reducing the risk that water could become over-fluoridated.