Oats are sold in a variety of forms in supermarkets and health food shops, including steel-cut oats, rolled oats, quick-cook oats and instant oats. Whilst wholegrains do reduce blood sugar spikes, the way oats are manufactured does alter its effect on blood sugar. Some oats are better than others!
An article in the British Journal of Nutrition in 2015, investigated 20 clinical studies using human volunteers, the ingestion of different types of oats, and their glycaemic index (GI). Steel cut oats had the least disruption of the groat tissue, hence the starch was encased in the cell wall. Instant oats and quick oats contain more pre-gelatinised starch, have a smaller size, leading to a faster breakdown in the gut by stomach enzymes. The GI’s of the different oats are as follows:
|Type of Oat||Glycaemic Index|
|Steel Cut Oats||55|
|Large flake Oats||53|
So if you have insulin resistance or diabetes, it may be better to switch to rolled, large flake or steel cut oats. The additional cooking time may be better for your blood sugar levels!