They also don't increase blood glucose levels. So it is fair to count them as being different than sugars such as glucose or sucrose.
But unfortunately, as Rocky2 pointed out, except for xylitol they also differ in how they act in the GI tract. The difference can also include inducing loose stools or even diarrhea if the amount consumed is at all substantial.
Xylitol however is rarely used because it is expensive and not very sweet.