Xylitol is a naturally occurring sugar substitute that is often used medicinally to prevent dental cavities, treat dry mouth, and prevent ear infections in young children. It appears to work by inhibiting bacterial growth and decreasing the level of certain cavity-causing bacteria in saliva and dental plaque. Although it is a "natural" product, xylitol can still cause side effects, such as diarrhea and gas.
Xylitol is a sugar substitute. It is a "natural" product (not an artificial sweetener) found in various plants such as raspberries and strawberries. Most commercial xylitol is made from birch trees. It is often used in sugar-free candies and gums. Medicinally, xylitol is claimed to be helpful for preventing dental cavities, treating dry mouth, and preventing ear infections in young children.
(Click Xylitol Benefits for more information on possible uses.)
Xylitol is a sugar alcohol. It does not contain any carbohydrates, but it is not calorie-free (although it contains fewer calories than sugar). It is useful as a sugar substitute for people with diabetes because it does not cause the significant rise in blood glucose (blood sugar) caused by real sugar. Nor does it seem to affect insulin levels in humans.
Xylitol may prevent dental cavities in several ways. It seems to decrease the level of certain cavity-causing bacteria in the saliva and dental plaque. It also decreases the acid production by the bacteria, decreases the stickiness of the bacteria, increases saliva flow, and increases calcium and phosphate in the saliva. All these actions can help to prevent cavities. Interestingly, habitually chewing gum with this sugar substitute can help mothers reduce the chance of transmitting cavity-causing bacteria to their young infants.
Xylitol may also inhibit bacterial growth (since most bacteria cannot use it as a source of energy), which might be why it may be useful for preventing ear infections.