Eating more nutritious food is probably just as important as staying away from sticky, sugary, cavity-causing foods. Carrots, just one example of foods that give your oral health a boost, can act like a toothbrush by scraping away some of the bacteria and plaque on teeth. High in beta-carotene, carrots may also lower your risk of oral cancer. (There is also evidence that beta-carotene may even help people who already have some forms of oral cancer.) In one study, just 30mg of beta-carotene a day (about 2½ carrots) produced improvement in up to 70% of cases of people with leukoplakia, the white lesions in the mouth that can mark the early stages of oral cancer.