Sneezing is your nose’s involuntary response to a nasal irritation. Traditions abound concerning sneezing, and many are rooted in cultural beliefs about the power of a sneeze. “God bless you,” for example, may have originated with the belief that your soul left your body when you sneezed and that evil spirits could enter unless a blessing was bestowed upon you. Or, that your heart stopped momentarily during a sneeze, essentially killing you for an instant, so you needed to be blessed.
One rational explanation for the exaggerated attention paid toward sneezing comes from the 6th century, when the Black Plague killed half the population of Europe. Sneezing was a symptom of the disease and was viewed as a sign of impeding death. People thus began to say “bless you” in hopes that the sneezer would not succumb to the infection, or, some say, as a final blessing.
Because sneezing is a common phenomenon and rarely harmful, little research has been conducted to demystify the sneezing experience. However, observational evidence, anecdotes, and a few studies provide insight into some common beliefs about sneezing.
Although it may seem that your heart takes a break during a sneeze, this is actually not the case. When you first inhale before sneezing, the pressure in your chest increases. Then, as you exhale forcefully during the sneeze the pressure drops. Alterations in blood flow to your heart produced by these pressure changes can affect the heart rate. However, the electrical activity in the heart marches on unimpeded–you remain very much alive throughout your sneeze!
Because most people’s natural reflex is to close their eyes when they sneeze, it is a common belief that blinking while sneezing is necessary. In fact, the nerves that go to your eyes and nose are closely connected, and stimulating one could conceivably generate a response in the other. However, there is no real reason that your eyes must be shut when you are sneezing, and some people are actually capable of keeping their eyes open during a sneeze.
Not true. The few people who can naturally keep their eyes open while sneezing manage to keep them firmly inside their head. Also, holding your eyes open with your fingers when you sneeze has not been reported to cause serious eye problems. Most importantly, there is no physical mechanism involved in a sneeze that could make your eyes pop out. While blood pressure behind the eyes may increase slightly during a sneeze, this small, brief force is nowhere near enough to dislodge them from their boney sockets. This is a good thing, since your eyelids would probably be incapable of holding your eyeballs in if a sneeze was actually strong enough to dislodge them.
This is one of the many myths about preventing pregnancy. The theory behind the sneezing idea is that if a sneeze is powerful enough to shoot mucus out of one’s nose, it must be strong enough to expel the semen from a woman’s vagina after sexual intercourse. However, although some semen may be expelled after a very powerful sneeze, even the most outrageous sneezing fit wouldn’t get rid of enough semen to provide reliable contraception.
According to one study, approximately 30% of people suffer from so-called “photic sneezing” triggered by looking at a bright light. The response seems to be acquired rather than inherited, and for most people it is not a consistent phenomenon (they won’t sneeze every time they look at the sun). The cause of photic sneezing is still unknown, but some researchers speculate that bright light triggers the nerves involved in sneezing by stimulating the retina or pupil, or by causing the person to squint. In susceptible people, such stimulation crosses the nerve signals that normally induce a sneeze. Photic sneezing can’t hurt you, and it may actually help when you feel a sneeze coming on and want to get it over with!
When you sneeze, the air that you expel is estimated to be traveling at around 100 miles per hour. Trying to hold in such a strong force (by pinching your nose, for example) pushes the air into the Eustachian tube, which connects to the middle ear and eardrum. Redirecting a sneeze like so could theoretically result in a ruptured eardrum and loss of hearing, which would be expected to resolve as long as the practice isn’t repeated. This is different than holding back an impending sneeze from occurring in the first place, for which there is no known associated harm.
Although many superstitions associate sneezing with danger or even death, sneezing is just a natural reflex, much like itching and tearing. Most of the rumors about sneezing are not true. Your heart does not stop, people can sneeze with their eyes open, and pregnancies can and do occur despite a sexually active sneezer’s best efforts. There is at least one useful truth to be found among all these sneezing myths: once you do it there’s no turning back. If you block a sneeze, you may not be able to hear your much deserved “God bless you.”
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Why do we say ‘bless you’ after a sneeze? Inspiration Line website. Available at:http://www.inspirationline.com/Brainteaser/sneeze.htm. Accessed November 10, 2008.
Why do we sneeze with our eyes shut? Flipside Extra website. Available at:http://www.flipside.org.uk/say/lowdown/. Accessed November 10, 2008.
Image Credit: Nucleus Communications, Inc.