Rolled Oats vs Quick Oats – What’s the Difference?

Rolled oats, also known as old fashioned oats, start out whole (as all oats do) with the grain and the husk in tact. The husk is the covering that encases each grain. This gets removed, and the remaining product is called the oat groats.

The groats are steamed and flattened between heavy rollers (hence the name rolled oats) then dried in a kiln. This drying process adds flavour and stabilizes the healthy oils in the oats by deactivating an enzyme that can cause the oats to go rancid.

Old fashioned oats are the most common type of oats found around the world.

Quick oats also start out whole with the grain and husk in tact. To produce quick-cooking oats, the same process of removing the husk followed by steaming and flattening the oat groats occurs.

In this case the groats are steamed for a longer period of time before rolling, and when they are rolled, the rollers are closer together creating a thinner oat product. These thin oat pieces are also cut up which creates more surface area for faster cooking.

Because they’re cooked longer and rolled thinner and smaller in the manufacturing process, quick oats cook more quickly (which is why they’re called quick oats) than rolled oats do.

Rolled oats are steamed for a shorter period of time and rolled into larger, thicker flakes. Quick oats require more processing to produce, as they are steamed for a longer period of time and rolled then cut into thinner, smaller flakes.

Because of their smaller size, quick oats have a greater surface area and can absorb liquid more quickly than rolled oats, thus cooking faster when preparing dishes like oatmeal or porridge. And because rolled oats are larger and thicker, they will take a bit longer to cook and/or absorb liquids.

Despite the differences in processing, there are marginal nutritional differences between rolled oats and quick oats. Plain rolled oats and plain quick oats contain similar amounts of nutrients like fat and protein, with very slight differences in carbohydrates, fibre, and calories. Quick oats do have a slightly higher glycemic index compared to rolled.

This table provides a nutritional breakdown of rolled oats vs quick oats per 1/2 cup serving:

According to the International Glycemic Index Database, rolled oats have a glycemic index score of 59, while quick oats have a glycemic index of 66. Both 59 and 66 fall within the medium glycemic index range.

Because quick oats have a higher GI, they can raise your blood glucose levels slightly quicker compared to rolled oats. This is due to the smaller size of the oats.

Generally you can use rolled oats and quick oats interchangeably in recipes like baked goods and smoothies, though there may be some slight texture differences. Same goes for your morning bowl of oatmeal, although quick oats will of course cook more quickly as they absorb liquid and soften more easily.

When it comes to recipes like overnight oats, rolled oats and quick oats are not interchangeable.

Here at Hannah Magee RD, we share all kinds of simple and nutritious oats recipes, including overnight oats.

Because quick oats absorb more liquid than rolled oats, they are more likely to become soggy in overnight oats where the oats are sitting in liquid like milk and yogurt overnight. I have made overnight oats using quick oats before. The taste is usually good, but they do tend to be more on the soggy side.

Rolled oats are perfect for overnight oats. Due to their larger size and thickness, they tend to absorb just the right amount of liquid for a creamy but still chewy overnight oats texture.