You may have heard 1000+1 reasons not to swallow your gum, but if you did, it won't kill you, nor will it stay in your stomach for seven years…. 
The risks of swallowing gum are greatly exaggerated.
Gastroenterologist Mark Larson tells Greatist that he always swallows his gum.
“I just hate the idea of taking it out and putting it somewhere,” he says.
Your body does the same thing with gum, as it does with anything else, it can't digest it, like all fiber. It just pushes it out.
So where does the myth come from? It probably comes from a real, but rare, phenomenon called a bezoar. A bezoar describes a mass of undigested food (or non-food) that's stuck in your stomach or intestines.
A cat often gets it from hair that it cannot digest.
Although bezoar is a real phenomenon, it is so rare that there are only three cases reported in the medical literature.
