How can drinking tap water prevent me from getting cavities?

Tap water that has been treated with fluoride can prevent cavities. Studies show that community water fluoridation prevents at least 25 percent of tooth decay in children and adults.

While teeth are forming under the gums, the fluoride taken in largely from drinking water and other beverages strengthens tooth enamel making it stronger and more resistant to cavities. 

After teeth erupt, fluoride helps rebuild (remineralize) weakened tooth enamel and reverse early signs of tooth decay. When you brush your teeth with fluoride toothpaste, or use other fluoride dental products, you are providing a “topical” benefit because the fluoride is applied to the surface of your teeth.

In some cases, tap water has been treated with fluoride, which helps keep your teeth strong. Drinking tap water in this case can be better than drinking water from other sources since the tap water has been infused with fluoride to promote dental health. However, even if you only have bottled water available, drinking water after eating will still help your teeth. Water helps rinse away residual sugars in your mouth that could cause cavities.

Tap water itself will not prevent you from getting cavities, but the fluoride it contains will. The fluoride in tap water strengthens your enamel and makes it more resistant to acid-producing bacteria, which causes cavities. The fluoridation in tap water is a great way to ensure your children are protected from tooth decay. Today, more and more people are drinking bottled water, which contains no fluoride, so it is important to still drink the proper amount of tap water.