A diet rich in sugary sweets increases your chances of developing cavities. Tooth decay occurs when enamel, the protective coating on your teeth, starts to break down. Eating junk food with a high sugar content, such as soda, candy and baked goods, coats your mouth, gums, tongue and teeth with sugar. This sugar coating attacks enamel and leads to tooth decay and cavities. Avoid having a painful trip to the dentist by eliminating sugary snacks from your diet. If you drink soda, switch to a sugar-free variety. Lessen your risk of tooth decay by brushing your teeth after each meal or snack