In 2015, most of us take our oral health for granted. Nearly everyone has a full set of teeth (unless you play a lot of hockey). This was not the case in the early 1900s, when oral health in the United States was a big problem. Ten percent of World War II recruits were rejected because they did not have at least six opposing teeth. And it was common for an affluent bride or high school graduate to receive a gift of dentures. School children typically developed three to four new cavities each year, and it was normal for adults to have full extractions and receive complete dentures.
What made the difference between then and now? Why don’t we see this degree of oral decay today? The difference is due in large part to community water fluoridation, a practice that marks its 70th anniversary this year. Fluoridation is one of the top 10 public-health advancements, according to the U.S. Centers for Disease Control and Prevention (CDC), saving Americans an estimated $38 in dental treatment costs for every $1 spent fluoridating. So why is this issue so often the subject of heated debates? A little historical and scientific background is helpful.
Fluoride is a naturally occurring mineral. In fact, some studies label it as the fifth most abundant element in the earth’s crust. Fluoride caught the interest of public health folks right here in Colorado in the early 1900s, when a young dentist, Dr. Frederick McKay, opened a dental practice in Colorado Springs. He quickly noticed that many local residents were showing up with discolored teeth. Not finding anything about this in the literature, McKay began to study. He discovered the discoloration to be a result of naturally occurring fluoride in the drinking water. More importantly, McKay observed that these stained teeth were surprisingly resistant to decay.
Years later, the City of Grand Rapids, Michigan, was convinced of the benefits of optimal fluoride intake and began fluoridating its community water supply. A cohort study was initiated to observe the difference in the occurrence of cavities between children growing up in Grand Rapids and Muskegon, Michigan. Fifteen years into the study, the kids in Grand Rapids had 50-70 percent fewer cavities, and the parents in Muskegon demanded that the study stop and that their water be optimally fluoridated so their children could receive the same benefit.
Today, the benefits of community water fluoridation are not as obvious, because fluoride is consumed in other ways as well, such as in toothpaste, foods and bottled drinks. It is frequently at optimal levels in bottled drinks because most bottling plants are located within cities that optimally fluoridate their water. But even with these other sources of fluoride in our lives, community water fluoridation continues to be effective in reducing dental decay by about 25 percent. Studies have shown that the benefits of fluoride are best realized when it’s ingested. That way, the fluoride ends up in the saliva, protecting teeth 24 hours a day.
Community water fluoridation is endorsed by the American Academy of Pediatrics, the American Medical Association, the American Dental Association and the World Health Organization. Yet even after more than 70 years of scientific study, the practice continues to generate debate. A quick Google search on the subject will turn up conspiracy theories of communist brainwashing plots, purported links to decreased IQ and other myths about fluoride.
Those who assert that fluoride is toxic are, in fact, 100 percent right. At high levels, it is indeed toxic. As with medications or dietary supplements, there is a beneficial amount, and there is a toxic amount. The bottle of ibuprofen in my desk drawer instructs, “The smallest effective dose should be used … Do not take more than six tablets in 24 hours.” It can be beneficial to take one or two ibuprofen tablets to relieve a headache. However, taking more than six tablets in a day can damage your liver. The same principle applies to fluoride. Research has shown that 0.7-1.2 parts per million (ppm) is the smallest effective dose, depending on the climate you live in. This is why many municipal drinking water systems fluoridate to this level. In Summit County, these include the town of Breckenridge, the town of Dillon and the town of Silverthorne water systems. The maximum level allowed by the U.S. Environmental Protection Agency is 4.0 ppm.
It’s important to know how much fluoride is in your home’s water for two reasons. First and foremost, water with natural fluoride levels above 4.0 ppm should not be consumed. It is possible that water from some private wells in Summit County could contain fluoride at these levels. Dental fluorosis — the discoloration Dr. McKay observed in Colorado Springs — can occur when young children consume too much fluoride (from any source) over long periods of time. Second, you should know whether there is sufficient fluoride in your water to receive the substantial oral health benefits this mineral can offer.
Customers on public water systems can simply call their water department to find out what their fluoride levels are. Information on many of the public drinking water systems in Summit County can also be found on the Summit County Public Health website at www.co.summit.co.us/drinkingwater. Households on private wells can have their water tested. Testing can be performed by private laboratories and at the Colorado Department of Public Health and Environment. The cost is typically about $17 to $20. If your water lacks optimal fluoride levels, talk with your doctor, who can prescribe fluoride supplements for you or your children to ensure that your family’s oral health is appropriately safeguarded.
Summit County Environmental Health works to control environmental factors that impact human health and the environment. We address issues such as food sanitation, air quality, water quality and communicable diseases. Environmental Health is a division of Summit County Public Health, which provides services to prevent disease and to promote and protect the health of the community.
Dan Hendershott is the Summit County Environmental Health manager.