Ahhhhh…choo! We all know that familiar sound. It's the sound of someone sneezing, and it's often accompanied by a spray of saliva and other fluids from the nasal cavity.

Of course, when you sneeze, you usually don't see those fluids being expelled from your nose. Why not? Because your eyes are closed! If you've ever thought about it or watched other people sneeze, you know that the eyes automatically close right before the sneeze explodes from the nose. But why is that?

If you ask children on the playground at school, some of them may tell you a wild tale. For many years, an urban legend has made its way from school to school. It usually goes something along the lines of “if you sneeze with your eyes open, your eyes will pop out of your head." Could there be any truth to this claim?

Fear not, fellow sneezers! The act of sneezing — also known as sternutation — will not cause your eyes to pop out, even if you do sneeze with your eyes open. And, yes, it is possible to sneeze with your eyes open. It's just very difficult and you have to make a concerted effort to keep your eyes open. Some people who try to sneeze with their eyes open can only accomplish this feat if they hold their eyelids open!

This curious phenomenon occurs because the eyes automatically close when you sneeze as a result of one of the body's involuntary reflexes. That means your brain sends a signal to your eye muscles to close your eyes before a sneeze without you ever thinking about it or doing anything.

Some believe this reflex developed to prevent what is being sneezed out from getting into the eyes during the process. Others believe it's simply a reflex with no particular purpose whatsoever.

When you sneeze, it's usually because there's something tickling or irritating the inside of your nose. Common irritants can include dust, cold air, and pepper, as well as swelling and irritation from a cold, the flu, or allergies. Like a cough removes unwanted particles from your throat and lungs, sneezing is your body's way of removing unwanted particles from your nasal passages.

In addition to your brain, other parts of your body, including your abdominal muscles, chest muscles, diaphragm, and throat muscles, combine to expel air quickly out of your nose to clear the unwanted particles. Scientists estimate the material leaving your nose during a sneeze can travel at up to 100 miles per hour!

That's a lot of pressure behind a sneeze, but don't worry. Your eyeballs are safe. First, the passageways and muscles involved in a sneeze aren't connected to your eyes. More importantly, your eye muscles that control your eyeballs keep them firmly in place at all times.

Eye doctors would even tell you that your eyelid muscles aren't strong enough to keep your eyeballs in place if they were being pushed out of their sockets. Luckily, you don't have to worry about that happening as a result of a simple sneeze!

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