Steel Cut vs. Rolled Oats: Which is Healthier?

It’s no secret that oatmeal is a healthy breakfast but with so many types of oats to choose from it can certainly make things a little confusing. From steel-cut to rolled to quick-cooking to instant, there are so many different forms of oats available to us and you might be surprised to learn that they are a lot more similar than they are different. Here is everything that you need to know about steel-cut vs. rolled oats.

The Difference Between Steel-Cut and Rolled Oats

All oats begin as whole grains. Once harvested, the external husk of an oat kernel is removed, leaving the bran, the germ, and the endosperm intact. Unlike other grains, oats rarely have their bran or germ removed. Instead, the oat kernels, which are sometimes referred to as oat groats, can be made directly into different types of oats.

Steel-cut oats are made by slicing the oat groats into 2 or 3 smaller pieces with a steel blade, hence the term “steel-cut”. This process allows water to more easily penetrate the oat and reduces cooking time. (1) Steel-cut oats tend to have a coarser and chewier texture and nuttier flavor than other forms of oats, and typically take the longest to cook. Steel-cut oats are sometimes referred to as Irish oats.

Rolled oats are made by steaming and flattening oat groats with a roller, as opposed to cutting them with a blade. The more oats are steamed and flattened the quicker they cook and the softer their texture becomes. (2) Because they have been steamed and rolled, rolled oats are quicker to cook than steel-cut oats and can be used to make even quicker cooking versions such as quick oats and instant oats. Rolled oats are sometimes referred to as old-fashioned oats.

Other Types of Oats

In addition to steel-cut and rolled oats, oats can be found in many other formats, including:

Scottish Oats: Instead of cutting the oats with a steel blade, Scottish oats are made by stone-grinding oats groats, resulting in broken oat bits of various sizes.

Quick or Instant Oats: By rolling rolled oats thinner and/or steaming them longer you can further reduce the cooking time to create quick-cooking or instant oats.

Steel-Cut vs. Rolled Oats Nutrition

Both steel-cut and rolled oats are good sources of carbohydrates and fiber and a moderate source of protein. Here is a comparison of one serving (44 grams) of steel-cut vs. rolled oats. (3)(4)

CALORIES: A serving of steel-cut oats contains 160 calories, while a serving of rolled oats contains 174 calories.

PROTEIN: A serving of steel-cut oats contains 5.0 grams of protein, while a serving of rolled oats contains 5.5 grams of protein.

FAT: A serving of steel-cut oats contains 2.0 grams of fat, while a serving of rolled oats contains 2.7 grams of fat.

CARBOHYDRATES: A serving of steel-cut oats contains 31.0 grams of carbohydrates, while a serving of rolled oats contains 30.2 grams of carbohydrates.

FIBRE: A serving of steel-cut oats contains 4.0 grams of fiber, while a serving of rolled oats contains 4.6 grams of fiber.

SUGAR: A serving of steel-cut oats contains 1.0 grams of sugar, while a serving of rolled oats contains 0.9 grams of sugar.

As you can see, steel-cut oats and rolled oats contain very similar nutritional values.

Benefits of Steel-Cut and Rolled Oats

Source of Nutrients

In addition to being a source of carbohydrates, fiber, and protein, both steel-cut and rolled oats are a rich source of thiamine (B1), magnesium, phosphorus, zinc, as well as iron, copper, manganese, and selenium. (5)

Fiber

Oats are a source of both soluble and insoluble fiber. Most notably they are a source of beta-glucan; a form of soluble fiber which has been shown to have numerous health benefits. (6)

Gluten-Free

Oats are an inherently gluten-free grain, making them a good source of complex carbohydrates for those who are allergic to gluten or those who cannot consume it for health reasons. However, depending on where they are processed, oats may come into contact with other grains, or machinery used to process other grains, therefore, certified gluten-free oats will be labeled as such. (7)

Other Factors to Consider

Glycemic Index

Steel-cut oats have a slightly lower glycemic index ranking than rolled oats, 52 compared to 55, however, both the difference is very minimal and both versions rank low on the glycemic index scale, which is defined by a ranking of 55 or less. Instant and quick-cooking oats rank higher on the GI scale, with a ranking of 65, so steel-cut or rolled versions may be a better option for those concerned with blood sugar. (8)

Use

When making a bowl of oatmeal or porridge, both steel-cut and rolled oats are great choices. However, if you are looking to incorporate oats into baked goods, granolas, cookies, bread, or pastries, rolled oats are the best option given their texture and versatility. Steel-cut oats are best for slow cookers and crockpots.

Cooking Time

Steel-cut oats take longer to cook than rolled oats, roughly 20 minutes compared to 5 minutes, so if you are in a rush rolled oats are likely the best option.

Texture and Taste

Steel-cut oats have a denser and chewier texture and a nuttier flavor than rolled oats. Since rolled oats are steamed and rolled during processing, they tend to have a softer and mushier texture.

The Bottom Line

Steel-cut oats and rolled oats are nutritionally very similar. Both steel-cut oats and rolled oats are good sources of carbohydrates, fiber, protein, and nutrients. When choosing oats it is best to opt for natural, unsweetened oats, of any format, and limit versions with added sugar and preservatives such as instant flavored oats.