THE FLUORIDATION of public water systems in the U.S. since 1945 is often hailed as one of the great public-health advances of the century. Today, many children reach adulthood without a single cavity.
But now health researchers are questioning whether Americans, particularly children, may have too much fluoride in their diets. The U.S. Centers for Disease Control and Prevention just completed a study, to be published early next year, showing that children are exposed to fluoride from a variety of sources, including drinking water, toothpaste, fluoride supplements and even grape juice. “There probably is excess exposure,” says Kit Shaddix, fluoride team leader at the CDC’s division of oral health.
For years, groups have opposed the fluoridation of public water systems, blaming fluoride for ailments ranging from allergies to cancer. But the CDC is quick to say excess fluoride causes problems that are cosmetic, with no other adverse health consequences. Fluoride does occur naturally in many foods, including tea.
The CDC says the biggest problem is an apparent increase in dental fluorosis, an unsightly and permanent discoloration of teeth. Fluorsis is caused by overexposure to fluoride at a time when teeth are just forming, often leaving them stained brown with white spots. Only children under six years old are vulnerable. A recent national study found that 22% of U.S. children have some form of fluorosis. Bleaching can’t fix it. Dentists often use expensive veneers to cover the teeth.
Fluoride toothpastes are among the culprits. Two years ago, Colgate-Palmolive paid a family in Britain a “goodwill” payment of 1,000 pounds (about $1,600) after a child developed a severe case of fluorosis. And, well-meaning parents often put a large glob of toothpaste on their children’s toothbrush.
CHILDREN UNDER six should only use a pea-size amount of paste –something that is clearly explained on toothpaste labels. “That message has not gotten across,” says Dr. Shaddix, who blames toothpaste ads showing generous amounts of toothpaste squeezed onto the brush.
The other problem is that while many parents struggle to get children to brush their teeth, other youngsters like the taste of toothpaste too much. That’s the problem Dan Lundy, an Ellington, Conn., computer programmer, has with his three-year-old daughter Rebecca, who has a penchant for Aquafresh toothpaste. “She likes to eat it,” says Mr. Lundy. Her parents always supervise her brushing.
Some toothbrush manufacturers are stepping in to help parents solve the problem. Colgate recently introduced a new “My First Colgate Toothbrush,” featuring the Barney cartoon character. The head of the brush is smaller than a regular toothbrush, and includes a dot of blue bristles, to help children measure the right amount of toothpaste.
Last year, the Food and Drug Administration required toothpaste companies to put an additional warning on toothpaste labels telling parents to seek professional advice or contact a poison control center if a child swallowed too much toothpaste. Terry Loftus, a spokesman for Procter & Gamble, which makes Crest, says adults need to use the large amounts of toothpaste often shown in ads, but children are warned not to.
“Toothpaste with fluoride is considered an over-the-counter drug,” he says. “Parents should supervise their children under six” when using it.
That message surprised Cathy Murray of Middletown, N.J., who struggles to get her five-year-old daughter Christel to brush. “You think more is better,” says Ms. Murray, whose dentist did advise her daughter to use a small amount of paste.
ANOTHER PROBLEM , says the CDC, is that some doctors are overprescribing fluoride supplements for children. The Lundys give their daughter a supplement because the family uses well water, which isn’t fluoridated. But the CDC says doctors often give children under six fluoride supplements even though their homes are hooked up to fluoridated water systems. An estimated 62% of public water systems in this country are fluoridated, and the CDC estimates that as much as 25% of the children in the country take fluoride supplements.
“A whole lot less need supplements,” says Dr. Shaddix. “Pediatricians and dentists routinely give out fluoride supplements in fluoridated areas. But you put those two together, and you could get a big problem with fluorosis.”
The CDC also wants doctors and dentists to get a better idea of a child’s eating and drinking habits before prescribing supplements. Some foods –such as grape juice and tea — contain more fluoride than fluoridated water. Some grape juice has fluoride content of as much as 1.7 parts per million, compared with one part per million in fluoridated water. Teas can have between two and 10 parts per million of fluoride. Colas, soft drinks and juices that are bottled in areas where the public water supply is fluoridated also contain fluoride.
The CDC is calling for new labeling rules requiring manufacturers to list a product’s fluoride content. There’s no quick fix. But parents can check with health departments about whether local water is fluoridated. Dr. Shaddix says the most important step is to supervise children while they brush their teeth to make sure they’re spitting out the paste, not swallowing it.
If the kids brush regularly and use fluoridated water, there’s probably no need for supplements. If parents fear their child isn’t getting enough fluoride, they should talk with their doctor about other possible sources, such as juice and colas, before resorting to supplements.
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