Although chewing gum technically has no expiration date, it does lose flavour and become harder, brittler, and harder over time. When chewed within four to six months of when it was manufactured, gum tastes the greatest.
Due to its nonreactivity and low moisture content, chewing gum is typically exempt from having an expiration date. Chewing gum is still safe to chew, even after it has dried out and turned brittle.
People all across the world have enjoyed chewing gum for a very long time. Tree resin was used to create the first varieties of chewing gum. There is historical evidence of people chewing on tree resin going back more than 5,000 years.