Erythritol looks like sugar and sweetens like sugar but has almost no calories and only a negligible effect on blood sugar. Erythritol is technically a sugar alcohol or polyol. It may be unfamiliar to you, but erythritol has been part of the human diet for thousands of years due to its presence in fruits and some mushrooms. NOW Erythritol is 100% pure and derived from a corn source and is a great sugar alternative for diabetics. Eyrthritol, like Xylitol, may also inhibit cavities by denying plaque bacteria the fuel (sugar) it needs to erode tooth enamel.