Why Does Sugar-Free Food Act Like a Laxative?
J.S. Smith, Hamilton, New Jersey
Nina Watson, RN, MSN, CDE, responds: A wide variety of artificial sweeteners are used in sugar-free foods. A number of symptoms have been attributed to the presence of these additives in food, and whether or not you experience those symptoms may depend on your individual sensitivity to different types of sweeteners.
The primary culprits that cause the laxative effect are sugar alcohols, also known as polyols. Sugar alcohols come from plant products such as fruits and berries. They have what is called an osmotic effect. They act much like the concentrated fructose (the form of sugar in fruit) that is found in prunes. The fructose pulls fluid into the gut, and when it's ingested in large amounts, it can result in bloating and diarrhea. Most people can tolerate sugar alcohols only in small amounts. Some of the common ones include mannitol, sorbitol, xylitol, lactitol, and maltitol.
Some of the other sweeteners have been reported anecdotally to cause diarrhea as well, although no scientific studies have found a connection. A sensitivity to or intolerance of artificial sweeteners may produce other symptoms, too. If you do experience problems with bloating, diarrhea, or other symptoms after consuming artificial sweeteners, you should limit or avoid the foods that contain that product. Also, remember that a sugar-free food item is not necessarily calorie- or carbohydrate-free. Be sure to read the nutrition label and consider how that product fits into your daily meal plan.
Updated on Nov. 29, 2010