You heard about it in Healing Points close to a decade ago!

Sugar Substitute Xylitol Reduces Risk Of Cavities: "he sugar substitute xylitol affects the bacterial composition of the oral cavity even in low doses. On the other hand, a relatively high intake is needed to counteract the production of acid between the teeth, according to Pernilla Lif Holgerson in the dissertation she will defend at Umeå University in Sweden on February 23.

Xylitol is a sugar alcohol that is produced by reduction of the sugar xylose, or wood sugar. Xylitol occurs naturally in fruits and berries, such as pears and strawberries. It is used in sugarless sweets, above all in chewing gum and lozenges. The dissertation studies what effects the substance has on the ecology of the oral cavity and its role in preventing tooth decay (caries). In a series of studies on children and adolescents, samples of saliva and plaque were examined. Among other findings, it was determined that a daily intake of 3.4 grams of xylitol was sufficient to change the consistency of the bacteria, but this did not lead to a lower production of lactic acid in plaque. In another study it was shown that a single higher intake of xylitol for a limited time reduced the degree of acidity in plaque between teeth."