Chewing gum contains the natural sweetener xylitol, which can help reduce chronic ear infections, say researchers from the University of Oulu, Finland. About 300 pre-school children were given chewing gum, half containing xylitol and the rest plain gum. The incidence of ear infections fell by 50 per cent in those chewing the xylitol gum. Xylitol is known to prevent tooth decay because bacteria which thrive on fructose and glucose apparently cannot live on xylitol. Researchers say that xylitol also appears to prevent bacteria from attaching to cells at the back of the mouth that enter the ear and cause infections.