Oats are among the healthiest grains you can eat. They provide a good amount of protein, fiber and fat, as well as a wide variety of vitamins and minerals. This makes oats an excellent choice for a healthy breakfast. Studies have shown that oats can help reduce your blood sugar levels and lower your risk of heart disease. Even though they are one of the healthiest foods and an excellent addition to your diet, oats are also high in starch. (1 C (81 g) = 46.9 g of starch, or 57.9% by weight) Tooth decay can happen when foods containing carbohydrates (sugars and starches) are left on the teeth. Bacteria that normally live in the mouth change these foods, making acids. The combination of bacteria, food, acid, and saliva form a substance called plaque that sticks to the teeth. Over time, the acids made by the bacteria eat away at the tooth enamel, causing cavities.