I have tested my blood sugar right after, 1 h after and 2 h after drinking coffee with stevia in it. There was no change in my blood sugar. Now, I don't know if there was a change in my insulin or if I was tempted to eat something sweet after (I am not drawn to sweets). I have hashimotos. I have heard that it can raise insulin in theory. Maybe I am an odd duck. Stevia surely beats sugar IMO.