When I was working on Lose Weight Weight the Smart Low-Carb Way, the nutritionist Bettina Newman and I considered including xylitol in some recipes but eventually decided against it because this sugar sub is really best in small amounts only. Like other sugar alcohols (sorbitol, mannitol, etc.), xylitol is not as easy to digest as sugar and pulls water into the intestines to help with digestion. This can cause diarrhea if you eat too much. It can also create unpleasant gas because bacteria in the colon ferment sugar alcohols. Xylitol is mostly used in small amounts in things like chewing gum and toothpaste. I wouldn't recommend using it in large amounts for baking, but if you use small amounts, it's best to keep some sugar in the recipe and only substitute xylitol for about half the amount of sugar called for.