In particular, oats are a good source soluble fibre can help reduce cholesterol and helps keep blood sugar levels steadier—which is helpful for managing and preventing diabetes as well as keeping your appetite in check.
Steel Cut Oats
These are the least processed type of oat cereal. The toasted oat groats are simply chopped into chunks about the size of a sesame seed.
Because steel cut oats are so much chewier and denser and also somewhat less processed than rolled oats, you might expect that their glycemic load would be lower. However, the differences between steel cut and roll oats are really not that big. Steel cut, stone ground, and rolled oats are all in the same ballpark as far as glycemic load goes.
These are made by steaming the toasted groats and then running them between rollers to create flakes. Rolled oats can be eaten as is or cooked into oatmeal.
Because they go through some extra processing steps, you might assume that rolled oats would be less nutritious than steel-cut oats, but it turns out that the differences are quite minor. Steel cut, stone-ground, old-fashioned, and quick-cooking rolled oats are all made from whole grains and they all have approximately the same amount of fibre, protein, calories, and other nutrients.
Instant or Quick-Cooking Oats
These are simply rolled into thinner flakes, so they cook a little faster.
Instant oats: These are the most heavily processed. The groats have been chopped fine, flattened, pre-cooked, and dehydrated. Instant oatmeal usually has added salt and sugar. I suggest leaving the instant oats on the shelf. In the time it takes you to boil the water to make instant oatmeal, you can cook some old-fashioned oats in the microwave.
The glycemic load of quick-cooking and instant oats, is quite a bit higher than that of rolled or steel-cut oats. That means that a bowl of quick-cooking or instant oats might not keep you satisfied for as long as rolled or steel-cut oats would. Nonetheless, as long as you stay away from the ones with the added sugar, quick-cooking and instant oatmeal are still considered low-glycemic carbohydrates.
What's the difference between instant, rolled, Old Fashioned, and thick rolled oats?
How far apart the rollers are set. No other prep work is done to the oat. The thinner the rolling, the quicker the oats cook because of the greater surface area of the grain. That's why my favourite way to cook oats is not to boil the grain itself, but to boil the water, add it to the oats and cover them, letting them set for 3-5 minutes. 1 part boiling water to 1 part rolled oats is a good ratio to start with. Add more or less water to suit your tastes.