Fluoride - is it necessary? Is it safe? This article from EverydayHealth is a great overview of why fluoride is added to our drinking water.
Most communities in the United States drink from fluoridated water supplies, but the benefits and risks are still being hotly debated. Here's what you need to know.
You’ve heard about fluoride from your dentist — there are fluoridated toothpastes, mouth rinses, even supplements. But do you know what fluoride is?
Fluoride is found naturally in water (rivers, lakes, streams, and oceans) and in many foods, such as grapes and tea. It’s also added to certain processed cereals and infant formulas. And this mineral has a big benefit: It protects your teeth from the plaque bacteria and sugars that hang around your mouth after you eat, preventing tooth enamel from being eaten away and cavities from forming.
In fact, evidence suggests that fluoride not only prevents decay, but also reverses it by enhancing re-mineralization, the rebuilding of tooth enamel that has begun to decay. That’s why the American Dental Association (ADA), as well as most dentists, believes that small amounts of fluoride should be added to water supplies so that everyone gets an adequate amount.
The scientific evidence is quite clear, says Howard Pollick, BDS, MPH, a professor in the department of preventive and restorative dental sciences at the School of Dentistry at the University of California in San Francisco, and a spokesman for the American Dental Association. “Fluoride prevents tooth decay,” he says.
However, others believe that adding fluoride to water supplies is unnecessary and dangerous. A recent government study found that about two in five teens have dental fluorosis — white spots and streaks on their teeth — from consuming too much fluoride.
A Short History of Fluoride
On Jan. 25, 1945, the city of Grand Rapids, Mich., was the first to add fluoride to its municipal water supply. Studies had shown that children had fewer cavities if they lived in areas where the water contained more fluoride. Today, nearly three-quarters of Americans live in communities with fluoridated water supplies.
Dr. Pollick says that many communities have less than 0.3 parts per million of fluoride in their water — less than what U.S. public health officials recommend for the prevention of tooth decay.
However, fluoride today is more widely available in toothpastes, mouthwashes, and rinses, as well as in a gel, foam, or varnish that dentists can apply to teeth, than it was in the mid-1940s when communities began fluoridating their water.
Government health officials recently acknowledged these changes in lifestyle and lowered the recommend levels for water fluoridation. In January, the U.S. Department of Health and Human Services and the U.S. Environmental Protection Agency (EPA) recommended that the fluoride level in drinking water be set at 0.7 milligrams per liter of water. Their previous recommendation had been a range of 0.7 to 1.2 milligrams.
Still, Pollick says research shows that the benefits of fluoridation outweigh the risks and that, by fluoridating the water, children from poorer families who don’t have as much access to dental health care are at least consuming fluoride. Dental fluorosis is mostly a cosmetic issue that can be dealt with, he says, and there’s no evidence that fluoridation poses a cancer risk, as some activists claim.
“We’re confident,” says Pollick, who served on the EPA panel that recommended the changes, “that water fluoridation is safe and a cost-effective way of reaching an entire community.”
The Argument Against Fluoridation
Though the American Dental Association supports fluoridation, critics believe that any amount of fluoride added to water is too much — claiming it puts people at risk for adverse health conditions, including fractures, brain damage, and cancer.
“Water fluoridation is not safe,” says Kathleen Thiessen, PhD, of the Center for Risk Analysis at SENES Oak Ridge Inc. in Tennessee. “At levels of exposure typically encountered in the United States, even with the recent lower recommended fluoride concentration, people are exposed at or above a level that is associated with a higher risk of adverse health effects.”
Bill Osmunson, DDS, MPH, a general and cosmetic dentist in Bellevue, Wash., says that dental fluorosis is more than just a “cosmetic problem,” and it can be costly to treat. “Some patients pay $20,000 to $30,000 to have it repaired, and the repair doesn’t last forever," he says.
According to Dr. Osmunson, studies show that excess fluoride can cause fractures to teeth and bones, kidney damage, thyroid issues, heart disease, brain damage, and cancer. The amount of tooth decay that is seen doesn’t vary between communities where the water is fluoridated and those where it isn’t, Osmunson says. So, he asks, why put people at risk?
But according to the National Cancer Institute, the evidence from many studies done on fluoride exposure in both humans and animals shows no association between fluoridated water and risk for cancer. Adults who get too much fluoride have been shown to be at risk for a painful bone condition called fluorosis of bone — but this is exceedingly rare at the fluoride levels found in the United States.
ADA’s Bottom Line
According to the ADA, the new recommendation for fluoride levels should provide an effective level of fluoride that will continue to reduce the incidence of tooth decay in children and adults of all ages and incomes, while minimizing the rate of dental fluorosis.
If you have concerns about fluoridation and want to avoid fluorosis, talk to your dentist.