There are different sweeteners in terms of glucose\insulin impact and effects on your body. Famous "explosive diarrhea" ***** bears have sweeteners inside them. Sweet drinks with aspartame seem fine if you don't have huge problems with your liver.
Stevia and erythritol are the overall best choices as far as I know, but they aren't that common.
Diabetic chocolate often has maltitol as sugar sub and people get explosive diarrhea on that too. Maltitol has variable glycemic index and sometimes has pretty significant on blood glucose. I've measured glucose eating chocolate with sugar and maltitol, sugar chocolate spikes me from 4.5-4.7 close to 6.0, and sugar chocolate spikes me to 7, sometimes closer to 8 at 1 hour mark. Quite a significant difference even considering that those numbers are considered healthy. I didn't have any GI issues after eating like 80g of maltitol chocolate in one go, but it might be different for you.