News & Press
John C. Chao, D.D.S., M.A.G.D
Faculty, USC School of Dentistry
Conquer Tooth Decay with Sugar?
Yes! A new kind of sugar, called xylitol, when incorporated into chewing gum, can not only prevent tooth decay, but may also help “re-mineralize” or heal small cavities that have not penetrated the enamel, according to an article published in the Journal of the American Dental Association (JADA). This article states, “The evidence is strong enough to support the regular use of xylitol-sweetened gum as a way to prevent caries, and it can be promoted as a public-health preventive measure.”
To understand how xylitol can prevent tooth decay it is important to understand how cavities are formed. Sugar does not directly cause cavities. Rather, sugar introduced into the mouth is converted into acid by bacteria (e.g., Streptococcus mutans) in dental plaque. The increased acidity of the plaque causes “demineralization” of the enamel, which is the highly mineralized, hard covering layer of the crown of the tooth. The reason xylitol is effective in preventing cavities is that its chemical properties does not allow microorganisms to convert it into acid. Furthermore, unlike common sugars, xylitol does not decrease the pH (increase acidity) in dental plaque that would result in more acid formation. In fact, chewing xylitol gum has been shown in some studies to lower plaque formation. Other studies seem to indicate that regular use of xylitol gum can “re-mineralize” enamel undergoing the initial stages of chemical breakdown.
Xylitol tastes almost the same as sorbitol-sweetened gum (“sugar free gum”). Xylitol, according to the JADA article, is more beneficial “in terms of reducing caries risk than does sorbitol-sweetened gum.” Sorbitol-sweetened gum is a “low cariogenic sweetener” rather than a “non-cariogenic sweetener”, such as xylitol.
Xylitol contains only 2 grams of sugar in two sticks of gum. Substituting some xylitol products in the diet can significantly reduce caloric intake. Consider the fact that the average consumption of all sugar is 141.5 pounds per capita in the U.S. in 2003. Much of the sugar intake has come in the form of sodas and juices, both of which have replaced milk and formula in the diets of infants and young children. The American Academy of Pediatrics has strongly opposed the practice of manufacturers of sodas and juices in contracting with school districts for the sole right to stock vending machines in the schools, known as “pouring rights.”
Another interesting discovery is that the regular use of xylitol may interrupt the transmission of cavity-causing bacteria from mother to child, according to a study from Finland. It was reported that there was a “significant reduction in the colonization of mutans streptococci” in the saliva of the infants in this study which involved 195 mother-infant pairs. The cavity rate of the children in the xylitol group was 70% lower than the other groups.
It is recommended by some dental experts that it is beneficial to have a regimen of chewing xylitol-sweetened gum three to five times a day for minimum of five minutes to inhibit plaque accumulation and chemical breakdown of enamel. In combination with regular home care and visits to the dentist, xylitol can be a beneficial adjunct to maintaining your smile for a lifetime. Check with your dentist as to whether xylitol may be right for you.