You've likely seen sugar alcohols listed alongside sugar on a nutrition panel and wondered what in the world those are. Are they dangerous to eat? Will they get you tipsy? The short answer to both: No.
What Are Sugar Alcohols?
Also called polyols, sugar alcohols are carbohydrates (like sugar) that provide about half the calories real sugar serves up, according to the Calorie Control Council.
Sugar alcohols are naturally occurring in trace amounts in certain foods such as fruits and vegetables (think pineapple, berries, sweet potatoes and asparagus), according to the U.S. Food and Drug Administration (FDA). But they're also commercially produced from sugars and starches; when they appear in a list of ingredients on the back of a packaged food, it means that they've been added to the food to boost its sweetness and/or improve its texture or moisture level.
Xylitol, erythritol, hydrogenated starch hydrolysates, isomalt, lactitol, mannitol, sorbitol and maltitol are all different types of sugar alcohols. And no, they do not contain any ethanol (the type of alcohol in your favorite happy-hour drink). Why the "alcohol" in the name, then? It's simple: Sugar alcohols have chemical characteristics of both sugars and alcohols, according to the FDA.
Sugar alcohols are different from artificial sweeteners or low-calorie sweeteners (LCS) in a few ways. For one, sugar alcohols contain some calories and carbs, while artificial sweeteners contain zero calories and carbs. What's more, artificial sweeteners (like those found in diet sodas) have been linked to weight gain, according to an April 2015 study published in the Journal of the American Geriatric Society, whereas sugar alcohols have not.
Benefits of Sugar Alcohols
"There are several potential benefits of sugar alcohols when they're used in place of added sugars," says Sheri Barke, MPH, RD, a performance and wellness dietitian based in Stevenson Ranch, California. "Because they provide half the calories of sugar, they can lower a product's calorie density and help with weight management." Compared to table sugar (sucrose), which contains four calories per gram, sugar alcohols contain between zero and three calories per gram.
What's more, because sugar alcohols also have a lower glycemic effect than other sweeteners, Barke says they don't raise blood sugar and insulin as much, which is especially important for people with diabetes. Erythritol and mannitol both have a glycemic index of zero — deeming them the best choice for people with diabetes — while maltitol has a glycemic index of 36. Foods with a high glycemic index have been linked to obesity and other metabolic diseases.
Unlike sweeteners such as cane sugar and high-fructose corn syrup, sugar alcohols are non-cariogenic, Barke adds, which means that they don't cause tooth decay. In fact, a January 2010 review in the International Journal of Dentistry found that sugar alcohols have the ability to prevent tooth decay via remineralization, promoting oral health. This makes sugar alcohols a prime ingredient in sugar-free chewing gum.
Just like dietary fiber feeds the good gut bacteria in your microbiome, so do sugar alcohols, according to a 2015 study in Critical Reviews in Food Science and Nutrition as well as a June 2010 study in Beneficial Microbes. Therefore, sugar alcohols can potentially provide some health-promoting prebiotic benefits.
Sugar Alcohol Side Effects
Just because sugar alcohols boast a lower glycemic impact and fewer calories than other sweeteners doesn't mean they're beneficial for everyone or that you should consume them with reckless abandon. "Sugar alcohols can increase our cravings for sweets and provide a delayed response to being satiated or a sense of fullness, as well as recognizing satisfaction," says Robyn Goldberg, RD, an intuitive eating expert in Beverly Hills, California.
You should also take caution with sugar alcohols if you have a gastrointestinal condition such as irritable bowel syndrome (IBS), Crohn's disease or ulcerative colitis_._ Sugar alcohols can have a laxative effect and can cause gas, bloating and diarrhea if eaten in excess, an October 2016 study in the International Journal of Dentistry found. The study also found that xylitol is better tolerated than other sugar alcohols, so it might be worth giving it a try.
Xylitol is highly toxic to dogs. According to a March 2012 study in Veterinary Clinics of North America: Small Animal Practice, xylitol can stimulate excessive insulin secretion in pups, leading to severe hypoglycemia (low blood sugar) and potentially death. Scan the ingredient lists in peanut butter, baked goods and other foods if you're sharing them with Fido.
Read more: Erythritol vs. Stevia vs. Xylitol
Are Sugar Alcohols Healthy to Eat?
If you tolerate sugar alcohols well and enjoy foods that contain them, apply the golden rule of nutrition: moderation, suggests an April 2017 report in Clinical Nutrition ESPEN.
Seek pleasurable ways to consume whole, natural foods while listening to your body, respecting its "full" and "hungry" cues. If you notice any digestive upset or increased sugar cravings, consider limiting sugar alcohols in your diet.
"Sugar-free candies, sugar-free frozen desserts and sugar-free protein bars may be void of sugar, but they may be high in saturated fat and/or low in health-promoting nutrients found in whole, unprocessed foods," Barke says. "So, whether you enjoy products sweetened with real sugar or sugar substitutes, enjoy them in moderation and focus on a high-quality eating pattern filled with fruits, vegetables, whole grains, legumes, nuts, lean proteins and unsaturated oils."
- Calorie Control Council: "Polyols Q&A"
- Clinical Nutrition ESPEN: "The Role of Artificial and Natural Sweeteners in Reducing the Consumption of Table Sugar: a Narrative Review"
- Critical Reviews in Food Science and Nutrition: "Xylitol: a Review on Bioproduction, Application, Health Benefits, and Related Safety Issues"
- Beneficial Microbes: "Synbiotic Effects of Lactitol and Lactobacillus Acidophilus NCFM™ in a Semi-continuous Colon Fermentation Model"
- International Journal of Dentistry: "Gastrointestinal Disturbances Associated with the Consumption of Sugar Alcohols with Special Consideration of Xylitol: Scientific Review and Instructions for Dentists and Other Health-Care Professionals"
- Veterinary Clinics of North America: Small Animal Practice: "Xylitol Toxicosis in Dogs"
- International Journal of Dentistry: "Sugar Alcohols, Caries Incidence, and Remineralization of Caries Lesions: A Literature Review"
- Journal of the American Geriatric Society: "Diet Soda Intake is Associated With Long-Term Increases in Waist Circumference in a Bi-Ethnic Cohort of Older Adults: the San Antonio Longitudinal Study of Aging"
- U.S. Food and Drug Administration: "Sugar Alcohols"