I'm sorry that this probably seems like a stupid question, but how are we certain that potato starch as bought on Amazon (e.g. Red Mill) is the same kind of 'raw potato starch' that researchers have been testing? When a journal paper on RS comes with an attribution at all, it's usually something that sounds technical and specialized, not "we bought this from the supermarket". Maybe all the potato starch we see on Amazon is cooked potato starch without the RS. Now, I know that you've apparently been testing potato starch in various ways, but suppose I didn't want to rely on that kind of indirect evidence. Do you know directly from any assays, tests, citations, etc. that store-bought potato starch is 80% RS?

I ask because I just bought the stuff (Red Mills untreated potato starch from Amazon), and took it with my MCT oil and protein powder, and I'm worried that my reaction to it may indicate that it's being treated by my system as carbs. Also, when I looked up the glycemic index of potato starch, it was listed as being close to 100. Maybe that presumes cooking, maybe it doesn't, but it worried me.

(I would very much prefer that the reply specify "Yes, we know directly the content of commercial 'potato starch'" or "No, we have only the indirect evidence from testing our blood glucose" before asking any further questions about my diet - for now I just want to know this part in the first step.)

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