That’s the problem with most substances with no caloric value, the body can’t absorb it and tries to get rid of it by inducing the shits. Your colon is like: “Wtf is this dude eating mud?”.
This is why those sugar-free gummy bears give people epic diarrhea, they are almost completely sugar replacements. The brain and nose/mouth love it, but the intestines can’t do anything with it and want to get rid of it ASAP.
I’m not sure there is a way to fix this, which is kinda sad because I really want to lose weight, but also stress eat sweets.
Reverse chirality sugar may be a way forward, but nobody has figured out how to make it cheap in large quantities.