Sugar alcohols are made from adding hydrogen atoms to sugars. They don't contain ethanol, so they're not related to alcoholic beverages. They can occur naturally in foods such as fruits and berries. Sugar alcohols have about one-half to one-third fewer calories than regular sugar, because they convert to glucose more slowly. They don't usually cause sudden increases in blood sugar, so can be used in moderation by diabetics. Some people with Type I diabetes have found that their blood sugars will rise if they consume sugar alcohols in large amounts.
The caloric content varies by specific sugar alcohol. Erythritol, for example, is not absorbed as easily as others, so it essentially has no calories. Some of the other sugar alcohols can have almost as many calories as sugar, so they're not necessarily used in "diet" foods, but in sugar-free gum.
Sugar alcohols are found in many sugar-free processed foods, such as hard candies, cookies, chewing gums, soft drinks, throat lozenges, toothpaste, and mouthwash. Look on product labels for mannitol, sorbitol, xylitol, lactitol, isomalt, erythritol, maltitol, and hydrogenated starch hydrolysates (HSH).
The FDA requires products that contain what would equate to a daily dose of 50 grams or sorbitol or 20 grams of mannitol to be labeled with a "laxative effect" warning. This is because higher levels of sugar alcohols unabsorbed in the intestines can cause bloating, gas, and diarrhea. According to the Center for Science in the Public Interest, only 10 grams of sorbitol can cause GI distress.
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