Yes, oatmeal with banana is healthy. Eating the combo provides you with a whole serving of carbs, fiber, and protein. Eating either one alone would provide you with only one carbo-based nutrient. This means that oatmeal and banana are often quite filling without consuming breakfast meats like bacon or sausage. Eating this combination can help regulate blood sugar levels because it includes complex carbs that are digested more slowly than your typical morning cereal or toast. The fruit will provide potassium which can help decrease your risk for stroke and high blood pressure while also helping control your heart rate and prevent irregular heartbeat thanks to its rich content of magnesium for relaxation purposes.