When the dentist had to fill six cavities in her 4-year-old son’s baby teeth, Amy Wilson was shocked.
The New York City mother of three scanned her family’s habits, trying to figure how Seamus, now 7, could have developed such tooth decay so early.
“We said, 'No, no, no, they don’t have candy or gum or soda regularly,'” recalled Wilson, 42, an actress, author and blogger. For a while, she was stumped.
But then, at a party, a dentist friend posed a surprising question: Did Wilson’s children drink bottled water?
“I had a dentist tell me to make sure to give my kids tap water and not bottled because the latter isn’t fluoridated, and he’s seeing kids with more cavities,” said Wilson, who posted on the popular blog, Type A Parent.
It turns out that many dentists and government health officials suspect that the practice of skipping tap water in favor of bottled water may be contributing to rising rates of tooth decay in young children.
“You should brush twice a day with a fluoride toothpaste, see the dentist twice a year for fluoride treatment and get fluoride in your drinking water,” said Jonathan D. Shenkin, spokesman on pediatric dentistry for the American Dental Association. “If you’re not getting it in your drinking water, that takes out a component of the effectiveness of that triad.”
The Centers for Disease Control and Prevention, too, warns that “bottled water may not have a sufficient amount of fluoride, which is important for preventing tooth decay and promoting oral health.”
No question, many kids do drink bottled water. One recent study in the Archives of Pediatrics found that about 45 percent of parents give their kids only or primarily bottled water, while another in the journal Pediatric Dentistry found that nearly 70 percent of parents gave bottled water either alone or with tap water.
More than 65 percent of parents using bottled water did not know what levels of fluoride it contained, that study showed.
At the same time, tooth decay appears to affect a huge swath of the nation’s young children. About 42 percent of children ages 2 to 11 in the U.S. had cavities in their baby teeth, according to a 2007 prevalence study, the most recent data from the Centers for Disease Control and Prevention.
The study tracked rising decay from 1988 to 1994 and then from 1999 to 2004, when it was up overall about 2 percent. The data showed that decay affected not only more than half of children at the lowest income levels, but also nearly a third of kids in higher-income families.
That supports additional research by Bruce Dye, a dental epidemiology officer with the National Center for Health Statistics, which actually found that boys in higher income families had the greatest prevalence of decay. Whether that's because it's harder to get those boys to brush, or because parents in higher-income families are more likely to provide more beverages, such as juice, sports drinks -- and bottled water -- isn't clear.
“I look at that as choices being made,” Dye said. “Gatorade or bottled water could be part of that.”
To be clear, there are no studies to date that document a clear tie between bottled water and tooth decay. And the International Bottled Water Association, an industry trade group, notes that at least 20 of its roughly 125 bottlers do offer fluoridated bottled water -- and that water is a healthier option than other beverages.
“In fact, bottled water does not contain ingredients that cause cavities, such as sugar,” the IBWA said in a statement responding to a recent New York Times story about a rise in dental surgeries among tots.
But Shenkin and other dental experts say it’s actually not clear whether there’s a link between bottled water and tooth decay, mostly because the issue hasn’t been studied because of a lack of funding for oral health research.
They contend that the continued popularity of bottled water in the U.S. -- about 8.4 million gallons a year or about 27.6 gallons per person in 2009, according to the Beverage Marketing Corp. -- fuels concern about kids’ consumption.
“I look at it as parents trying to do the right thing, trying to be healthy, but being healthy doesn’t prevent [cavities],” said Dye.
Fluoridation of public water supplies has been hailed as a public health victory, but in recent years, many U.S. communities have voted to stop adding it to local drinking water. Fluoride protects against tooth decay, but it also can cause tooth discoloration and bone weakness if ingested at too high levels for many years, experts agree.
Federal regulators last year proposed setting recommended fluoride levels in drinking water to the lowest end of a range that permits between 0.7 and 1.2 milligrams of fluoride per liter of water, but officials are still wrestling with finding a balance between preventing decay without harming teeth and health.
Meanwhile, inadequate brushing habits, delayed dental visits, poor choices of foods and snacks and bad beverage selection -- in addition to spotty consumption of fluoride -- all likely contribute to tooth decay, Dye said.
No matter what causes it, the problem with decay that starts early is that it often gets worse.
“When you have tooth decay in your baby teeth, you will have tooth decay in your permanent teeth,” said Dye.
The problem may be particularly worrisome in minority families, who were three times more likely than others to give their kids only bottled water, usually because of concerns about the safety or taste of their home tap water.
Kids in minority families also are more likely to have tooth decay. The CDC data showed that 55 percent of Mexican-American kids ages 2 to 11 and 43 percent of black children had cavities in their baby teeth. For white youngsters, the figure was about 37 percent.
For all families, the key is to make dental health a priority, Shenkin said. Babies should see a dentist by age 1 and brushing twice a day with a fluoride-containing toothpaste should start at age 2.
“As soon as that first tooth comes through in the mouth, it’s susceptible to decay,” he said. “If you wait until kids are 3 or 4 years of age, it’s already happened.”
For Wilson, who admits tooth brushing is a struggle with kids now aged 4, 7 and 9, awareness has been a big part of changing her family’s habits.
“We live in New York City where the tap water tastes fine,” she said.