Our stomach does not digest gum at all. The reason why gum is not digested in the stomach is because it is made out of soluble fiber. Chewing gum passes right through us together with the rest of your waste.
It definitely does not take 7 years to digest gum. Some enterprising mother must have come up with that story to scare their children away from swallowing this sticky treat, or maybe, moms themselves cut their teeth on this myth as children. Gum, although classified as indigestible, will still pass through the digestive tract and out the other side, as everything that goes into your mouth must do