Sugar alcohols, or polyols, are carbohydrates used as sweeteners. Common ones include erythritol, xylitol, sorbitol, maltitol, and mannitol. They occur naturally in some fruits and vegetables and are also manufactured for use in foods, drinks, and sugar-free gum.
They provide fewer calories per gram than sugar and have a lower impact on blood glucose, though the effect varies by type. Products marketed for weight or blood sugar management often use them. Xylitol, for example, is added to dental products because topical exposure can reduce cavity-causing bacteria.
Because the small intestine does not fully absorb them, sugar alcohols can cause gas, bloating, or diarrhea, especially at high intakes. Tolerance differs from person to person. Some people get symptoms after just a few grams. Xylitol is extremely toxic to dogs.