Why We Accidentally Spray Saliva When We Yawn

Imagine that you have a superpower — but instead of the ability to fly or move objects with your mind, it’s something inconsequential and probably useless. The truth is, humans actually have their fair share of superpowers, like hysterical strength, when in life-and-death situations people manage to perform beyond their limits. And on the “weird” side of the spectrum, we have the ability to... spit really far.

We at Bright Side find some of the whimsies of our body amusing and want to research this strange phenomenon for you.

What is gleeking

Gleeking proudly takes a spot somewhere at the top of gross things the human body can do accidentally. Gleeking is shooting a jet of saliva from under your tongue, much like a venomous snake. You can even do it on purpose if you really put your mind to it, as numerous schoolyard pranksters have proven throughout history.

How saliva works

Gleeking happens when a large amount of saliva builds up in your mouth below your tongue: for example, if you’ve eaten something sour or bitter. Saliva is secreted by the major salivary glands. If you look in the mirror while raising your tongue, you can see the ducts that deliver saliva from the glands to the mouth.

Gleeking is achieved by compressing these ducts with muscles in the base of the mouth when you move your tongue upward. If your mouth is wide open the stream can be launched several feet.

What happens when we yawn

Your mouth has a heap of muscles, and sometimes you can be doing some mouth thing — like talking or eating — and hit just the right combination, and whoosh, there it goes. When you get a yawn attack, you accidentally squeeze the salivary glands under your tongue, forcing the saliva to squirt out in a spray. Luckily, people can’t gleek again until the ducts are refilled.

Why do we need this

Funnily enough, we don’t. There’s no reason why evolution gave it to us — aside from wanting to have a good laugh at us while we find ourselves in an awkward position. The ability to gleek is a ridiculous byproduct of evolution, rather than an end-goal. It doesn’t serve any physiological or social purpose — except, of course, impressing your friends with how far and precisely you can project that gush.

But hey, at least you will learn to close your mouth when yawning to avoid this display of saliva archery.

Has gleeking ever happened to you? What other awkward moves have your body pulled all of a sudden?