Steel-cut oats, rolled oats, and quick oats differ by the amount of processing they undergo. Each can be part of a nutritious diet.

When thinking of a healthy, hearty breakfast, a hot bowl of oats might come to mind.

There are several types to choose from, including rolled oats, steel-cut oats, and quick-cooking oats, which differ in their nutrient profile and processing methods.

This article explains the key differences between these varieties so that you can decide which one makes the most sense for your diet and lifestyle.

Steel-cut, rolled, and quick oats start out as oat groats, which are oat kernels that have had tough outer shells removed.

Oat groats are exposed to heat and moisture to make them more shelf-stable (1).

The oat groats are then processed in different ways to create either steel-cut, rolled, or quick oats, all of which have distinct characteristics.

Steel-cut oats

Steel-cut oats are most closely related to the original, unprocessed oat groat (1).

Steel-cut oats have a coarser, chewier texture and nuttier flavor than rolled or quick oats.

They also take longer to prepare, with average cooking times ranging from 15–30 minutes.

Rolled oats

Rolled oats, or old-fashioned oats, are oat groats that have gone through a steaming and flattening process (1).

They have a milder flavor and softer texture and take much less time to make than steel-cut oats, as they have been partially cooked.

Quick oats

Quick oats or quick-cooking oats are rolled oats that go through further processing to decrease cooking time.

They’re partially cooked by steaming and then rolled even thinner than old-fashioned oats (1).

They cook within a few minutes and have a mild flavor and soft, mushy texture.

Summary

Steel-cut oats have a chewy texture and nutty flavor, while rolled and instant oats are milder with a softer texture. Steel-cut oats are the least processed of the three.

Oats are rich in fiber and protein, plus packed with vitamins, minerals, and antioxidants (2).

Additionally, oats are naturally gluten-free. However, people with celiac disease should choose varieties that are certified gluten-free to avoid those that may have been contaminated with gluten during processing (3).

Just a half cup, or 40 grams (g), of dry, rolled oats contains (4):

  • Calories: 152
  • Protein: 5 g
  • Fat: 3 g
  • Carbs: 27 g
  • Fiber: 4 g
  • Thiamin: 15% of the Daily Value (DV)
  • Iron: 9% of the DV
  • Magnesium: 13% of the DV
  • Phosphorus: 13% of the DV
  • Zinc: 14% of the DV
  • Copper: 18% of the DV
  • Selenium: 22% of the DV

Oats are also loaded with beneficial compounds, including antioxidants and beta-glucan, a type of soluble fiber linked to health benefits (2).

For example, the beta-glucan found in oats is effective at lowering both LDL (bad) and total cholesterol, which may help keep your heart healthy.

One study of 80 people with high cholesterol found that consuming 70 g of oats for 28 days led to an 8% reduction in total cholesterol and an 11% reduction in LDL (bad) cholesterol (5).

Additionally, oats have been shown to aid weight loss and stabilize blood sugar levels (6, 7).

The beta-glucan in oats helps slow digestion, leading to an increased sense of fullness and a more gradual spike in blood sugar (6).

Summary

Oats are highly nutritious and have been associated with a number of health benefits. Eating them may help lower cholesterol, decrease blood sugar levels, and aid weight loss.

The variety of oats on the market can make it difficult to determine the healthiest option.

The chart below compares the nutritional differences between a 1.4-ounce (oz) or 40-g serving of rolled, steel-cut, and quick oats (4, 8, 9):

Rolled oatsSteel-cut oatsQuick oats
Calories150150150
Carbs27 g27 g27 g
Protein5 g5 g5 g
Fat3 g2.5 g3 g
Fiber4 g4 g4 g
Sugar0 g1 g1 g

As you can see, the variations between these three oat varieties are slight. However, there may be some distinctions between steel-cut, rolled, and quick oats.

Quick oats have a higher glycemic index

Steel-cut and rolled oats may have a lower glycemic index than quick oats (10).

Foods with a high glycemic index cause more rapid spikes in blood sugar, while foods lower on the glycemic index provide a slower release of energy and can help stabilize blood sugar (11).

For this reason, steel-cut or rolled oats may be the best choice to support better blood sugar control.

However, quick oats can also be included in a balanced diet by pairing them with toppings high in protein or fat, such as nuts or seeds, to support blood sugar control (12).

Summary

Steel-cuts and rolled oats have a lower glycemic index than quick oats, potentially making them the best choices for blood sugar control.

All three types of oatmeal are highly nutritious and can fit into a well-rounded diet. Therefore, the most important thing is to choose oatmeal that fits best with your lifestyle and preferences.

For example, the chewy texture and nutty flavor of steel-cut oats may be delicious to some but too hearty for others.

Meanwhile, rolled and quick oats have a milder taste and cook down to a creamy, smooth consistency.

And since steel-cut oats are the least processed, they take the most time to prepare, which could be a turn-off for some people.

No matter what type of oat you choose, opting for plain, unsweetened oats instead of flavored packaged varieties can help limit your intake of added sugar.

Too much added sugar can contribute to a number of conditions, including heart disease, diabetes, and obesity (13).

For this reason, consider adding your own toppings — such as fresh fruit, nuts, or seeds — to unsweetened oats to keep added sugar to a minimum.

Summary

Rolled, steel-cut and quick oats all provide a wealth of nutrition. Regardless of which type you choose, consider opting for unsweetened varieties to avoid excess sugar.

Although oats are most commonly consumed at breakfast, they can be a healthy carb choice at lunch and dinner as well.

Here are some ideas about how to make oats a part of your day:

  • Add raw oats to your smoothie for a fiber boost.
  • Use them in place of breadcrumbs to coat fish or chicken.
  • Incorporate oats into pancakes.
  • Use them in place of rice when making risotto.
  • Add them to soups to create creaminess without adding a lot of fat.
Summary

Oats are a versatile food that can be eaten at any time of day and added to both sweet and savory dishes.

Oats are a fiber-rich grain that has been linked to a number of health benefits.

Although rolled and steel-cut oats have a lower glycemic index, quick oats have a similar nutrition profile.

However, packaged instant varieties can contain a lot of added sugar, so it’s a good idea to choose plain, unsweetened oat varieties whenever possible.