I'm also looking for an answer. Xylitol is proven to increase pH in mouth, but I couldn't find evidence of its antacid influence on other "parts" of body, except: It enhanced levels of serum calcium and serum alkaline phosphatase activity and bone density in a rat model (source: Plosone, Protective Effect of Dietary Xylitol on Influenza A Virus Infection, Sun Young Yin, Hyoung Jin Kim, Hong-Jin Kim), but still I have no clue if it proves any antacid quality in human; I assume it should be lowering acidity, as it reduces Sugar in blood but I found no scientific paper on this issue; anyone could help?