Tooth decay has declined among young children in industrialized countries largely due to improved dental hygiene and the addition of fluoride to drinking water, toothpastes and mouthwashes. But dental cavities can still be a problem for individual children, adolescents and adults.

All common sugars, including those found in sweetened beverages, juice, milk, and sweet foods like cookies, as well as starches, such as those found in flour, bread, pasta and crackers, can contribute to dental cavities. In addition, acidic foods and beverages such as citrus juices, pickles and some soft drinks can contribute to the erosion of tooth enamel in some individuals if consumed frequently.

When foods or beverages containing sugars or starches are consumed, the bacteria in plaque, a sticky film of bacteria that constantly forms on teeth, produces acid that attacks tooth enamel. The stickiness of the plaque keeps the acid in contact with teeth. Over time and after many such attacks, the enamel can break down and a cavity forms.