All About Oats
There are more than a few different types of oatmeal to choose from. But not all oats are created equally in terms of the health benefits. In general, steel-cut oats have the lowest impact on blood sugar while instant or quick oats have the highest.
Sometimes referred to as Avena (from the Latin name, Avena Sativa), oats are one of the most popular breakfast foods. Walk into almost any breakfast restaurant and you’ll likely see some variation of oatmeal on the menu.
Despite their popularity today, oats were actually one of the last of the major grains to be domesticate - about 3000 years ago in Europe. This is likely due to the fact that they have a higher amount of natural fats and fat dissolving enzymes that make them go rancid quickly. It is these fats that give oats some of their health boosting effects.
The kind of oats that you eat are important, as the glycemic index can vary depending on how much they are processed and how they are prepared. In general, steel-cut oats have the lowest impact on blood sugar while instant or quick oats have the highest.
Steel-Cut Oats - (also known as Irish or pinhead) are whole oats that have been chopped into two or three pieces with steel blades. Uncut, they are known as oat groats. Steel-cut oats and oat groats are the least processed forms available.
Rolled Oats - are made by steaming the groats, then rolling them, steaming them again, and, finally, toasting them resulting in the familiar thin flakes. Though processed, rolled oats are still a whole grain. The cooking time for steel-cut oats is 20 to 40 minutes, compared to 10 minutes for rolled oats and 45 to 60 minutes for oat groats.
Instant/Quick Oats - are the most processed of the three oat varieties. They are partially cooked, dried, and then rolled and pressed thinner than rolled oats to allow the oats to cook more quickly. Often, these have skim milk powder, emulsifiers and other preservatives added to help them develop a creamy texture when you cook them. They have a more mushy texture, as they retain less of their shape when cooked.
Steel-cut oats are preferred because they digest more slowly than rolled or quick oats. Like all other grains in whole or cracked form, steel-cut oats rank lower than rolled oats on the glycemic index (GI), which ranks carbohydrate foods on the basis of how rapidly they affect blood sugar (glucose). Lower glycemic food are better in general compared to high glycemic foods - see my previous article Foods to Help Boost Your Metabolism, for the details on which foods are high and which are low on the glycemic index. The reason for this difference is that it takes longer for digestive enzymes to reach the starch inside the thicker pieces, slowing down their conversion to sugar.
The higher on the glycemic index a food ranks, the more likely it is to cause spikes in blood sugar. Over time, these rapid fluctuations can cause genetically susceptible people (most of us) to develop insulin resistance and metabolic syndrome. Insulin resistance is associated with obesity, high blood pressure, elevated blood fats, and an increased risk of type 2 diabetes. Glucose/Insulin spikes from high glycemic index foods also contribute to inflammation which may lead to cancer.
The bottom line - The key to which is the healthiest option comes down to the degree of processing. The less processed the oat, the lower the glycemic index as your body has to do the mechanical work of processing it (as opposed to the machine doing this). The coarser the oat, the more nutrition they contain and hence the better they are for us.
A frequent question that comes up is whether oats are gluten-free. Oats themselves are completely gluten-free, however the machines that process oats are often used for processing wheat as well. Unless the container specifically says “gluten free” the oats may contain trace amounts of wheat.