Source: Low Carb Luxury Magazine
Sugar alcohol is neither a “sugar” nor an “alcohol.” Sugar alcohols affect the blood glucose levels less dramatically than regular table sugar which is why some diet plans allow a certain amount of them. In most people, they quickly add up to too many carbs (they contain a little more than 1/2 the carbs than an equal amount of table sugar.) Because of U.S. labeling laws, products containing sugar alcohols (as well as other simple sugars such as fructose, lactose, maltodextrin, isomalt, etc.) can be labeled “Sugar Free.” This is a travesty in my opinion, so please remember to read labels ! You have to play detective yourself and read the ingredient label carefully.
Sugar alcohols available in the U.S. include Mannitol, Sorbitol, Xylitol, Maltitol, Maltitol Syrup, as well as hydrogenated starch hydrolysates, are found naturally in berries, apples, plums and other foods. They also are produced commercially from carbohydrates such as sucrose, glucose and starch.
While most of us low-carbers can get away with small amounts of sugar alcohols and keep to the diet, too many will get us into lots of trouble. Then there are the unpleasant “side effects” of sugar alcohols. They can cause abdominal discomfort and bloating and they also have a laxative effect. Consumption of 30 to 50 grams of sorbitol or xylitol, or 20 grams of mannitol, causes diarrhea in most people.
Is there a positive side to them? Yes. The inability of mouth bacteria to use them as a source of energy means they do not contribute to dental caries (cavities).
For your reference, less well-known sugar alcohols include: Galactitol, Erythritol, Inositol, Ribitol, Dithioerythritol, Dithiothreitol, and Glycerol.