It is an urban myth that terrifies young children: swallow a piece of chewing gum and it will take seven years to pass through your gut before it is digested.
But what does happen if you should accidentally eat a stick of gum? The gum base is pretty indigestible – it is a mixture of elastomers, resins, fats, emulsifiers and waxes. Most of the time, your stomach really cannot break down the gum the way it would other foods.
However, your digestive system has another way to deal with things you swallow. After all, we eat lots of things that we are unable to digest fully.
The gut just keeps moving them along until they make it all the way through the intestines and come out the other end.
So gum usually ends up in your lavatory one to two days later. Even though gum is sticky, it is usually no match for the power of your gut.
Our saliva will make an attempt at digesting chewing gum as soon as we put it in our mouths. It might penetrate the shell and sweeteners, but much of gum’s base ingredients are indigestible.
It's then up to our stomach muscles – which contract and relax, much like the way an earthworm moves – to slowly force the things we swallow through our systems.
Swallowing a huge wad of gum or swallowing many small pieces of gum in a short time can cause a blockage within the digestive system – most often in children, who have a smaller-diameter digestive tract than adults – but this is extremely rare.