Sugar alcohols aren’t really sugar or alcohol. Sugar alcohol used in many products is actually derived from high-grade maltose corn syrup. In fact, a sugar alcohol can look very much like a corn syrup. Though a process known as hydrogenation, the addition of hydrogen to the corn syrup, the "sugars" that make up maltose syrup are transformed from "sugar" into "itols or polyols" (polyhydric alcohols). So maltose, the sugar is now maltitol, the sugar alcohol. This polyol has a different chemical make-up than sugar and thus carries its new chemical name.
Polyols have other favorable attributes. Since maltose is now a sugar alcohol transformed into maltitol, it will metabolize in the body more slowly than sucrose (table sugar) and some maltitol will pass through the body without being metabolized at all. Thus, maltitol syrup will not cause the significant rise in blood sugar experienced when eating the same amount of sucrose.
For those individuals who are carbohydrate counting to control their blood sugar levels, still consider the total carbohydrates found on the food label. Remember that just because a product says sugar-free doesn’t mean it’s carb-free and the product may eventually contribute to the rise in blood sugar in the end.