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In addition to nonnutritive sugar substitutes, polyols (referred to as sugar replacers or nutritive sweeteners) are often used as alternative sweeteners. Nutritive sweeteners do not contain sucrose, but do contain sugar alcohols that sweeten and add bulk to various products. Unlike nonnutritive sugar substitutes, these sweeteners provide calories, although in lesser amounts than table sugar.

Sugar alcohols do not promote tooth decay or cause a sudden increase in blood glucose.  They may, however, have a laxative effect if consumed in excess.  Therefore, products containing large amounts of sugar alcohols must be labeled with the warning, “Excess consumption may have a laxative effect.”  

Sugar alcohols are classified as carbohydrates and appear naturally in fruits and vegetables. They may also come from substances such as glucose, starch and sucrose. Examples of polyols and the products in which they may be found include:

• Isomalt. Used in candies, chewing gum, ice cream, jams and jellies, frostings, beverages and baked goods.
  
  
• Lactitol. Used in candies, chewing gum, frozen dairy desserts, jams and jellies, frostings, baked goods.
  
  
• Maltitol. Used in candy coatings.
  
  
• Mannitol. Used as a bulking agent and found in chewing gum.
  
  
• Sorbitol. Used in special dietary foods, candies and gums.
  
  
• Xylitol. Used in chewing gum, candies, pharmaceutical and oral health products.

It should be noted that sorbitol also is made in the human body, and hyperglycemia encourages its formation. Sorbitol has trouble passing through cell membranes and can injure the cells. This damage has been linked to eyes diseases (diabetic retinopathy and cataracts), nerve disease (diabetic neuropathy) and kidney disease (diabetic nephropathy). However, dietary sorbitol is poorly absorbed and is not believed to cause diabetic complications. People with diabetes may safely consume polyols and artificial sweeteners in moderation, according to the American Diabetes Association.  

Tagatose is another type of nutritive sweetener. It is similar to fructose and derived from lactose. About 80 percent of tagatose is not absorbed until it reaches the large intestine, where bacteria chemically break it down and release gas and fatty acids that are absorbed by the body. It may be used in carbonated beverages, yogurts, chewing gum, mints and frostings.

Other products that use nutritive sweeteners include toothpaste and mouthwash.

The sweetness of nutritive sweeteners varies. They may be anywhere from 25 percent to 100 percent as sweet as table sugar. They often are combined with nonnutritive sweeteners to provide certain products an even sweeter flavor.

Nutritive sweeteners do not contribute to dental caries because bacteria do not convert them to acids. As a result, they are valuable in chewing gums, breath mints and other products that remain in the mouth for extended periods of time. They can affect blood sugar levels, but are absorbed slowly and incompletely and do not require much insulin to be metabolized. This makes them good alternatives to table sugar for people with diabetes.