Actually, zero calorie stuff is pretty much by definition stuff we haven't decided to "deal with". It doesn't get absorbed directly, and we never created a mean

Actually, zero calorie stuff is pretty much by definition stuff we haven't decided to "deal with". It doesn't get absorbed directly, and we never created a means to break it down into something that could be absorbed. The goal for a non-caloric sweetener is to be noticed by receptors on the tongue by chance while the rest of your body explicitly ignores it. Biological response is the "problem".