Harmful oral bacteria feed on the sugar you eat to form acids that erode tooth enamel. Enamel is the shiny, hard, protective outer coating of the tooth. Cavities are a bacterial infection that is created by acids that cause your teeth to have a hole in them. Cavities can drill past the enamel and into the deeper layers of the tooth, causing pain and tooth loss.
Lactic acid, which is made when bacteria in the plaque eats the sugar can harm teeth. Lactic acid lowers the pH level in the oral cavity and dissolves minerals from the enamel. The coating can then no longer fulfill its function as a protective jacket. The less sugar you consume, the lower the lactic acid production and there is less of a chance of tooth decay, resulting in an overall healthier oral cavity.