Authors: Don Becker and Robin Nwankwo
Source: Diabetes Forecast, July, 2005
My sister-in-law bought me “sugar-free” candy. Of course she didn’t read the nutritional information before she bought the candy, as I would have. When I read the nutrition label I was surprised to find that three pieces had 18 grams of carbohydrates! Where were all the carbs coming from? Under sugar, on the nutrition label, the total grams were zero. Under sugar alcohol, there were 18 grams, which explains where the carbs were coming from. How can anything be labeled as “sugar-free” if there is sugar alcohol in the ingredients? Sugar alcohol seems to have the same carbohydrates as regular sugar. Is sugar alcohol any better for people with diabetes than regular sugar? Don Becker, Dexter, Mich.
Robin Nwankwo, MPH, RD, CDE, responds: You were wise to look at the nutrition label for the total carbohydrate information. Let’s start by answering your questions in order. Sugar alcohols, when listed as ingredients, would include either mannitol, sorbitol, xylitol, lactitol, isomalt, maltitol, or hydrogenated starch hydrolysates.
Sugars would include honey, brown sugar, molasses, fructose, cane sugar, and confectioner’s sugar. The term “sugar-free” is an allowed U.S. Food and Drag Administration (FDA) nutrition claim to be used for foods containing less than 0.5 gram of sugar per serving.
Sugar alcohols, though listed by their weight content within the food as listed in the Nutrition Facts panel, are not metabolized (broken down and used for energy) the way true sugars are.
They are considered a reduced-calorie sweetener because they are absorbed slowly and incompletely by the intestine. Because sugar alcohols are incompletely absorbed, the FDA allows the labeling and assignment of less energy per gram to these nutritive sweeteners.
Sugar provides about 4.0 calories per gram, whereas sugar alcohols could provide from 0.2 to up to 3.0 calories per gram. Most professionals use the factor of 2.4 calories per gram, slightly more than half of what sugar would provide, to estimate energy provided. Typically, a product containing 10 grams of sugar alcohol is roughly equal to 5 grams of sugar (carbohydrate).
Looking at your gift of candy, with its 18 grams of sugar alcohol, you can plan on the candy yielding about 9 grams of carbohydrate as you eat your third piece. Sugar alcohols are thought to cause less of an insulin response in the body. Sugar alcohols can be useful for people living with diabetes because of the small calorie reduction as compared with sugar, along with smaller increases in blood glucose and insulin levels.
Sugar alcohols are also called polyols. They have been shown to not cause tooth decay. Of course, any food that provides calories can contribute to weight gain if eaten excessively.
One caution about sugar alcohol: If eaten in large doses (greater than 20 to 50 grams, depending on the type of sugar alcohol) it could lead to bloating and have a laxative effect.