Sneezing is one of the human body’s protective reflexes, just like coughing. When the insides of our nose gets irritated, such as pollen or dust, the tiny nerve endings inside the nose give a message to the brain, which in turn, gives a message to the various parts of the body to facilitate the sneeze.
When you sneeze, the chest muscles compress the lungs, which then send a burst of air upwards. The throat shuts tight, which sends the air shooting through the nose at speeds up to 100 mph. When you sneeze, you will release between 2,000 and 5,000 bacteria-filled droplets from the nose and mouth.
One popular myth is that one’s eyes will pop out if you sneeze with them open. It is not true at all, as our eyes are attached to the head very firmly. So our eyes are still attached when you forget to close them when you sneeze (although most of the people close their eyes instinctively when they sneeze because it is a normal body reflex).