Fluoride is often described as nature’s cavity fighter. By ensuring that your child gets the right amount of fluoride each day after her teeth start to erupt, usually between 6 and 12 months of age, you can help prevent tooth decay. But too much fluoride can discolor newly formed teeth, causing white or gray spots to appear—a condition known as fluorosis. Once teeth are completely visible in the mouth (around 8 years of age) there is no longer a risk for fluorosis. In the meantime, knowing how much fluoride to give and when can be challenging.
Most children and adults get their daily dose of fluoride from fluoridated toothpaste, mouthwash, and drinking water. Fluoride occurs naturally in water, but the level can be very low (less than 0.2 mg/L) or very high (more than 2.0 mg/L), so communities adjust the local water supply by adding or removing fluoride. The U.S. Department of Health and Human Services, in 2015, set the recommended level of fluoride for community drinking water at 0.7 mg/L, a decrease from the previous range (0.7–1.2 milligrams per liter) issued in 1962.
Infant formula manufacturers intentionally keep fluoride levels in infant formula low to guard against formula-fed babies getting too much fluoride when their formula is mixed with fluoridated water. According to the CDC, since 1979, U.S. infant formula manufacturers have voluntarily lowered the fluoride concentration of their products to less than 0.3 parts per million (ppm). However, when powdered or concentrated liquid infant formula is consistently mixed with fluoridated water, exclusively formula-fed babies can get too much fluoride. To prevent fluorosis in infants, parents are cautioned to use low-fluoride or fluoride-free bottled water (labeled as de-ionized, purified, demineralized, or distilled) when mixing infant formula for some of their child’s feedings each day. Parents can also use ready-to-feed formula that doesn’t require mixing with water. (Ready-to-feed formula, however, is much more costly than powdered or concentrated liquid formula.) The best way to prevent fluorosis is to monitor your child’s fluoride intake.
Fluoride supplements are not recommended for breastfed babies. Although some fluoride is delivered via breast milk, breastfed babies are not considered to be at risk for fluorosis unless they receive fluoride from other sources as well (supplements, formula mixed with fluoridated water, etc.).
How much fluoride toothpaste is recommended?
The latest recommendation from the American Dental Association (ADA) is for parents to use a “smear” of toothpaste (about the size of a grain of rice) for children under the age of 3 and a pea-sized amount for those 3 to 6 years of age. With the goal of simplifying fluoride guidance for parents, after an extensive review on the use of fluoride in children younger than 6 years of age, the ADA’s Council on Scientific Affairs reached two conclusions:
- Use of fluoride in children younger than 6 can reduce the incidence of caries (a.k.a. cavities).
- Ingestion of fluoride (pea-sized amounts or greater) at a young age can lead to fluorosis. While the risk of fluorosis in permanent teeth is associated with fluoride exposure from age 1, the risk to the permanent central incisors is greatest at about age 2.
The recommendation is a change from the ADA’s previous guidance, which encouraged parents to brush with water only, consult with a dentist or health care provider before using fluoride or fluoride toothpaste in children younger than 2 years old, and to use a pea-sized amount beginning at age 2.
Tips for monitoring your child’s fluoride intake:
- Consult a pediatric dentist within six months of your child’s first tooth erupting, and no later than her first birthday. The dentist should assess the child’s risk of developing caries, including a discussion of the child’s fluoride intake from all sources (toothpaste, beverages, supplements, etc.) as well as risk factors for developing caries.
- Brush children’s teeth twice a day, morning and night, using the appropriate amount of fluoride toothpaste. For children ages 6 months to 3 years, the American Dental Association (ADA) and American Academy of Pediatric Dentists (AAPD) recommend only a “rice grain–sized” amount of toothpaste at this young age. From 3 to 6 years old, they recommend only a “pea-sized” amount.
- Teach children to “rinse and spit” excess toothpaste from their mouth as early as possible. This reduces the risk of ingesting too much fluoride. By the time children are brushing with a “pea-sized” amount, they should be able to rinse and spit independently. (Note: Fluoride mouthwash is not an appropriate substitute for fluoride toothpaste and should not be used until age 6, except under the supervision of a dentist.)
- Supervise children in brushing their teeth until about age 6. Although many children will want to handle their own tooth brushing, parents should make sure the right amount of toothpaste is used, for the right amount of time (about two full minutes), and that all teeth are brushed.
- Forgo fluoride-free “training” toothpastes and mouthwashes. According to the ADA’s new guidelines, there is no reason to avoid fluoride since it can help prevent cavities with little risk of fluorosis, given an age-appropriate amount is used.
- Know your water’s fluoride level. If you live in a state that participates in the Centers for Disease Control and Prevention (CDC)’s My Water’s Fluoride program, you can check your water system’s fluoride level online or contact your local water supplier. If your drinking water contains more than 2.0 mg/L, the CDC recommends that you get your drinking water from another source due to the increased risk for fluorosis.
Although media reports can give the impression that fluoride is dangerous, such assertions are not supported by research. Parents simply need to know how much fluoride to give and when.