All oatmeal starts as whole groat oats, which are then processed to varying degrees. The process begins with heating and cooling the oat groats to help give them a nutty flavor. After this, oat groats are processed into ground groats, steel-cut oats, old-fashioned rolled oats, quick-cooking oats and instant oatmeal. Overall, oatmeal is one of the healthier breakfast items you can consume, but there are differences in nutrition with steel-cut oats compared to other varieties.
Steel-cut oats are made by cutting whole oat groats two or three times. The cut pieces of groats are neither steamed nor rolled. Since they do not go through this process, they are more intact than thick-rolled or instant oats. This causes steel-cut oats to have more surface area, which slows digestion. A larger surface area causes the stomach to work longer to break down steel-cut oats. The glycemic index, a measurement of the rise in blood sugar, is only 42 for steel-cut oats compared with 66 for instant oatmeal.
Oatmeal in general is a good source of B vitamins and vitamin E. Both vitamin groups act as antioxidants and help support healthy cell function. Additionally, steel-cut oats contain calcium, iron, protein and potassium. Calcium and potassium help support healthy blood pressure. Although steel-cut oats are processed less than other varieties, they contain only slightly more nutrients. Steel-cut oats do have more protein and calcium than old-fashioned and instant oats do.
Fiber helps you control your blood sugar levels and can provide satiety after a meal. Steel-cut oats have twice the amount of fiber per 1/4 cup than old-fashioned or instant oats have. Every 1/4 cup of steel-cut oats you eat provides you with 4 grams of fiber. Steel-cut oats can help you reach your daily goal of 25 to 30 grams of fiber, as recommended by the Academy of Nutrition and Dietetics.
Cooking Time vs. Nutrition
Steel-cut oats take longer to cook than other varieties with the exception of whole groats. On average, steel-cut oats take around 20 more minutes to cook than rolled oats. Instant oats may take as little as one minute to cook. Soaking steel-cut oats the night before can reduce the cooking time in the morning.