Turn over a package of "sugar-free" mints, chewing gum, protein bars or reduced-sugar baked goods, and you will often see an indented line beneath Total Carbohydrate labeled "Sugar Alcohol" (or a specific name like xylitol, erythritol, sorbitol or maltitol).
Despite the name, sugar alcohols contain no alcoholic ethanol—they are carbohydrate compounds used to add bulk and sweetness with fewer calories and a smaller blood-glucose rise than sucrose.
What sugar alcohols (polyols) are on U.S. food labels
As the U.S. Food and Drug Administration (FDA) explains in its consumer and regulatory overview of sweeteners in food, sugar alcohols (also called polyols) are a class of carbohydrate sweeteners permitted as sugar substitutes. Common FDA-recognized examples include sorbitol, xylitol, lactitol, mannitol, erythritol and maltitol.
Chemically, their structure resembles part sugar and part alcohol hydroxyl groups, Lock-free of ethanol (the alcohol in alcoholic beverages). According to the FDA, the sweetness of sugar alcohols ranges from about 25% to 100% as sweet as table sugar (sucrose), and unlike high-intensity sweeteners (such as steviol glycosides, monk fruit extract or sucralose, which are hundreds of times sweeter than sugar and used in tiny milligram amounts), sugar alcohols provide physical bulk and moisture texture in candies, cookies and chewing gums.
- Included under Total Carbohydrate: On the Nutrition Facts panel, grams of sugar alcohols are counted inside Total Carbohydrate, not under Total Sugars or Added Sugars.
- Calorie and dental profile: As the FDA notes, sugar alcohols are slightly lower in calories per gram than table sugar, do not promote tooth decay, and do not cause a sudden spike in blood glucose.
Why eating multiple servings of sugar alcohols can cause bloating or laxative effects
The reason sugar alcohols provide fewer calories than sucrose is that they are only partially or slowly absorbed in the human small intestine. The unabsorbed fraction travels into the large intestine, where it draws water into the bowel by osmosis and is fermented by colonic bacteria.
In small amounts—such as a piece of xylitol chewing gum or a single mint—most people notice no digestive effect. In larger portions—such as eating several "sugar-free" candies, chocolates or protein bars sweetened with sorbitol, mannitol or maltitol in one sitting—that osmotic water draw and bacterial gas fermentation can cause abdominal bloating, gas or a laxative effect. U.S. food labeling regulations even require a laxative warning statement on packages where foreseeable consumption of sorbitol or mannitol exceeds specific daily gram thresholds.
How to tell sugar alcohols apart from stevia, monk fruit and allulose on labels
Many reduced-sugar products blend a sugar alcohol (for bulk) with a high-intensity plant sweetener (to boost sweetness). Checking both the Nutrition Facts panel and the ingredient list lets you see which sweetener class is present:
- Look for the "-itol" ending in the ingredient list: Sorbitol, xylitol, erythritol, maltitol, mannitol and lactitol are all sugar alcohols.
- Distinguish high-purity steviol glycosides and monk fruit (Siraitia grosvenorii / Luo Han Guo extract): According to the FDA, these high-intensity sweeteners are 100 to 400 times sweeter than sucrose, so they are used in tiny amounts that add negligible grams or calories.
- Distinguish differently metabolized sugars (such as D-allulose, D-tagatose and isomaltulose): As the FDA explains, these meet the chemical definition of a sugar rather than a sugar alcohol, though they are metabolized differently by the body than sucrose.
Sources & Classical References
- FDA: Aspartame and Other Sweeteners in Food — Covers FDA-permitted sugar alcohols (sorbitol, xylitol, lactitol, mannitol, erythritol, maltitol), their 25%–100% sweetness relative to sucrose, lower calorie and dental/glucose properties, high-intensity sweeteners (steviol glycosides, monk fruit), and D-allulose/D-tagatose.
- NIH MedlinePlus: Carbohydrates — Provides background on carbohydrate digestion and how unabsorbed carbohydrates behave in the digestive tract.
