Few brands of bottled water add fluoride to their water, and the majority fail to contain optimal levels (0.7 to 1.2 parts per million) of fluoride necessary to protect teeth, according to the American Dental Association (ADA). Some brands use treatments that remove all of the fluoride in the water. Therefore, people who only drink bottled water are urged to talk to their dentist about ways to obtain fluoride from other sources. For example, they may need to use fluoridated toothpaste, rinse or a multivitamin with fluoride.

Consumers are urged to check the labels of bottled water to help determine whether or not the water contains adequate levels of fluoride for preventing tooth decay. The FDA requires bottled water with added fluoride to carry labels that say “fluoridated,” “fluoride added” or “with added fluoride.” The fluoride content of bottled water is not required on the label if fluoride is not added during processing. It may be necessary to directly contact the product manufacturer when trying to determine exactly how much fluoride is present in the water.

In 2006, the Food and Drug Administration (FDA) approved a health claim for fluoridated bottled waters. The claim “Drinking fluoridated water may reduce the risk of tooth decay” may be used on bottled water that meets certain standards and contains between 0.6 and 1.0 milligrams per liter of total fluoride. Total fluoride includes both naturally occurring fluoride and added fluoride. However, due to the risk of fluorosis, this claim may not be used on bottle water products marketed specifically for use by infants.

In addition, some home water treatment systems actually reduce the amount of fluoride in tap water, which can reduce the effectiveness of water in fighting cavities. Devices for treating water at home are available in two types. Point of use systems treat the water after it comes through the tap. They include devices that attach to the tap and water pitchers that use filters. Point of entry devices treat all water as it comes into the home.

Home water treatment systems vary in how much fluoride they remove from water. Steam distillation units remove 100 percent of fluoride content and devices that use reverse osmosis remove between 65 percent and 95 percent of fluoride. Meanwhile, the commonly used charcoal filters, carbon filters and water softeners generally do not remove significant amounts of fluoride. Consumers are urged to check with the manufacturer to find out whether or not a home water treatment system removes fluoride from the water.