When can you use fluoride toothpaste on toddlers?

From the time our children start brushing, we teach them to spit out their toothpaste rather than swallow it. But why (aside from the gross-out factor of swallowing a mouthful of toothpaste along with everything they've just brushed off their teeth) is it so important to spit?

Consumed in large quantities, fluoride can have toxic -- in extreme cases, even fatal -- effects on the body. The most common symptoms from an overdose of fluoride are gastrointestinal problems, including nausea, stomach pain, vomiting and diarrhea. At higher levels, fluoride poisoning can cause weakness, shallow breathing, convulsions and vomiting blood [sources: Crosta; A.D.A.M.].

Of course, swallowing only the amount used for brushing (a pea-sized drop, for children between the ages of 2 and 6) isn't likely to cause such a severe reaction, but consuming just a little too much each day for an extended time comes with its own set of concerns.

If children ingest too much fluoride over a long period while their permanent teeth are forming under the gums, they are at risk of developing dental fluorosis, a permanent discoloration of the tooth enamel [source: Centers for Disease Control and Prevention]. Dental fluorosis can range from mild, barely noticeable white spots on the permanent teeth to severe dark brown staining and even pitting of the teeth, in which small spots of enamel appear to have been chipped away. Fluorosis is a concern only for children younger than 8, because once the permanent teeth finish developing and break through the gums, they can no longer develop fluorosis [source: Centers for Disease Control and Prevention].

While the potential toxic effects of too much fluoride are certainly the scariest to read about, the dental fluorosis caused by long-term overconsumption of fluoride is far more common than acute fluoride poisoning. Fortunately, it's also fairly preventable, once you know it exists. Read on to find out how to protect your toddler's pearly whites.

Although your child shouldn't use fluoride toothpaste before the age of 2, chances are he or she is ingesting fluoride from other sources long before that. Fluoride is found in many foods, juices, and soft drinks and exists naturally to some extent in almost every water supply. In areas where the natural fluoride levels in the water supply are below the .7 parts per million (ppm) recommended by the ADA, municipalities often add fluoride to bring the water up to the desired level [source: American Dental Association].

Since a small amount of systemic fluoride (i.e., fluoride that is consumed or ingested rather than applied to the teeth) has been shown to be effective in reducing tooth decay, dentists and pediatricians will often recommend fluoride supplements for children over 6 months old whose water contains lower levels of fluoride [source: American Dental Association].

On the other hand, the "Journal of the American Dental Association" advises people living in areas where the fluoride levels in drinking water exceed 2 ppm to consider using bottled water or a water treatment system to reduce the risk of fluorosis in young children [source: Journal of the American Dental Association].

The toothpaste aisle of your drugstore or supermarket probably offers plenty of options for fluoride-free toddler toothpastes, but while these sweet-tasting cleaners (many of which feature popular cartoon characters on their packaging) might entice your child to brush, the CDC recommends simply using plain water and a small, soft-bristled toothbrush for children younger than 2 [source: Centers for Disease Control].

As your child approaches his or her second birthday, continue to reinforce safe brushing habits by reminding them to spit when they brush -- even if they're brushing only with water or fluoride-free "training toothpaste." At your child's two-year checkup, talk with the pediatrician about introducing fluoride toothpaste, then supervise brushing closely until you're confident that your child is reliably spitting -- not swallowing -- the toothpaste.

You'll need to call upon your best parenting patience here: According to the CDC, children have weak control over their swallowing reflex until age 6, so you'll most likely need to help for at least a few more years [source: Centers for Disease Control]. It's also important they use only the recommended amount of toothpaste -- that's a small, pea-sized amount, not a big stripe down the entire surface of the brush -- since despite all your best efforts, young children are still likely to swallow at least as much of the toothpaste as they spit out.