Preventing Tooth Decay - There are many factors that put us at risk for tooth decay, namely the numerous bacteria that reside in a normal, healthy mouth. The bacteria respond readily to starchy foods with processed sugars. After we eat such foods, bacteria produce acids that dissolve tooth minerals and cause cavities. Brushing frequently with fluoride toothpaste can greatly minimize this acid exposure, but timing is important. The acid exposure usually peaks 20 to 30 minutes following a meal or snack. If brushing is not possible, chewing sugarless gum can also help to reduce the acidic environment.