Not labeled as such, but here's Part 1: PhD Physical Chemist Commenter Marie is at it Again! Resistant Starch and Ketosis. Low Carb in Short Pants. There, we learn that while trying to keep her dad in ketosis for cancer therapy while upping his food choices to keep him in the game, she initially had difficulty.
Why? Well, resistant starch supplementation does improve fasting blood glucose. That's in the literature, and she duplicated it. It also blunts blood glucose spikes. That's in the literature—also: "lentil effect," "bean or legume effect," "second meal effect," etc.—too, but she was kinda only able to kinda duplicate that if V/0/LC and in ketosis.
Why? Here's probably why, in my view: