Jason E. Andersen

Bonus Fun Fact: You know how your stomach grumbles when you’re hungry? It does that all the time, you just don’t hear it.

Your digestive system is basically a hollow tube of varying diameter that runs from your mouth to your butt. Most of that hollow tubing is composed of smooth muscles that contract and relax, pushing the various contents along to their ultimate destination. When the muscles of the stomach and intestines contract, the various contents (food, undisclosed liquids, gasses, etc.) are churned up. The churning is what makes the sound and your body is constantly doing this. When you’re hungry, there are less solid and liquid contents held in your inner-workings, which makes the sound easier to hear.

Bonus Bonus Fun Fact: Like pretty much all things in biology, stomach rumbling actually has a name: borborygmus. If you know how to pronounce it, let me know.