Are all calories of suger alcohols absorbed or are some likely just ped through the GI tract?

i read that sugar alcohols aren't absorbed so is it truethat if a person eats an atkins bar -- for example-- with 130 calories, having about 80 or more of those calories comming from sugar alcohols, then those calories arent absorbed? Making the Atkins bar more like around 50 calories (130-80=50)? please go ahead and add any links you may know of too that could help answer this Q. :D