Does anyone know why people sneeze?

I know that we sneeze when we get dust up our nose, or inhale particles like pollen, or pepper.
But sometimes we sneeze when none of these things are present. So what makes us sneeze in these circumstances?
Answer:
Sneezing, also called sternutation, is your body's way of removing an irritation from your nose.

When the inside of your nose gets a tickle, a message is sent to a special part of your brain called the sneeze center. The sneeze center then sends a message to all the muscles that have to work together to create the amazingly complicated process that we call the sneeze.

Some of the muscles involved are the abdominal (belly) muscles, the chest muscles, the diaphragm (the large muscle beneath your lungs that makes you breathe), the muscles that control your vocal cords, and muscles in the back of your throat. Don't forget the eyelid muscles! Did you know that you always close your eyes when you sneeze?

It is the job of the sneeze center to make all these muscles work together, in just the right order, to send that irritation flying out of your nose. And fly it does - sneezing can send tiny particles speeding out of your nose at up to 100 miles per hour!

Most anything that can irritate the inside of your nose can start a sneeze. Some common things include dust, cold air, or pepper. When you catch a cold in your nose, a virus has made a temporary home there and is causing lots of swelling and irritation. Some people have allergies, and they sneeze when they are exposed to certain things, such as animal dander (which comes from the skin of many common pets) or pollen (which comes from some plants).

Do you know anyone who sneezes when they step outside into the sunshine? About one out of every three people sneezes when exposed to bright light. They are called photic sneezers (photic means light). If you are a photic sneezer, you got it from one of your parents because it is an inherited trait. You could say that it runs in your family. Most people have some sensitivity to light that can trigger a sneeze.

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Its a muscle spazm I believe

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From the dust that gets in their nose

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Sneezing usually occurs when the nerve endings of the mucous membrane of the nose are irritated, due to a swelling of the membrane, for example when we have a cold, or when some foreign body, such as a gnat, invades our nose, or when allergy and pollen season strike.

Surprisingly enough, sneezing can be brought on (or out!) when the optic nerves in our eyes are exposed to bright light!

For whatever reason, the membrane is irritated, sneezing is a reflex act, completely beyond our control, by which the nose trumpets out air in an attempt to eject (and project!) the irritating bodies. Sometimes, however, this is accomplished only through multiple sneezes.

Medical science dispelled ancient beliefs concerning the out-of-control sneeze, and snuffed out superstitions in the process. Primitive people held the belief that a sneeze signified approaching death, and immediately assisted the distressed person by crying out "God help you!" Egyptians, Romans, and Greeks, saw the sneeze as an omen of approaching danger, or, on a more positive note, as a way of foretelling the future. Lucky ones sneezed to the right, while unlucky ones sneezed to the left. The moral of the story is to know your right from your left, and to sneeze in that direction, regardless of who is next to you!

Biblically speaking, sneezing meant a certain death, until Jacob nosed in and made a deal with God, whereby a prayer per sneeze cheated the grim reaper. Pope Gregory the Great, in response to the sixth century plague in Italy, carved out his place in history as being the one responsible for insisting that prayers, such as "God bless you!," be said in response to the deadly sneeze. He did not, however, order that tissues be kept close at hand to snare the airborne germs spewed forth by the sneeze.

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Could b the tiny hairs up in your nose irratating it, there has to be something there irratating your nose really for you to sneeze. You may not b able to see dust but it can still b there also.

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yes, a sneeze is an irratation of the nose. when air is caught up in something such as pepper or basil; one unintentionally inhales and irratates the nose. why do we sneeze in these certain circumstances? for one there are billions of particles floating all around you at everysecond of the day. these particles contain samalian. this samalian is irratated to puppies, cows, and people. this bacteria is the most common cause of the sneeze.

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to get rid of all the rubbish in side

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I know exactly what you're talking about. The reason that happens is because there are always tiny bits of dust and stuff floating in the air. You can't see it, but it's there. When it's dark, look in the beam of a flashlight, and you'll be able to see all the bits of stuff floating around. That stuff goes in our nose when we breathe, and when too much gets in it, we sneeze and blow it out.

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