How many times were you told to "spit out your gum" at school? Well, now it turns out that chewing sugar-free gum can actually prevent cavities in children. New studies show that chewing sugar-free gum three to five times a day for five minutes each time can significantly reduce the number of cavities in children. However; not all sugar-free gum has the power to fight cavities. Look for gum that contains Xylitol, which is a "tooth-friendly" sugar alcohol used in some chewing gum and oral hygiene products.