The heat used in processing is key to the difference, high heat can affect nutrients. Steel cut oats are denser and have both soluble and insoluble fibre that is a boon to regular, healthy shits.
Being lower on the glycemic index shouldn’t be discounted either considering modern eating habits.
Heat can affect things like vit C but are not likely to significantly affect fibre levels... Not to disparage benefits of intact grains, but given how much more of a pain they are to prepare, if processed oats make people eat them instead of cereal, probs a good thing imo.
The heat used in processing is key to the difference, high heat can affect nutrients. Steel cut oats are denser and have both soluble and insoluble fibre that is a boon to regular, healthy shits.
Being lower on the glycemic index shouldn’t be discounted either considering modern eating habits.