Here's Looking Achoo! Debunking The Sneeze

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For such a commonplace bodily function, the sneeze has messed with our minds (and noses) for centuries. It will kill us, it won't kill us. We'll have bad luck, we'll have good luck. Watch out for Satan, he's wily and knows how to get into your nasal membranes. Did you have too much to eat? Are you sad? Do you have a weak heart?

Technically, sneezing is a reflex to the usual irritants such as germs, dust or pollen. But it turns out your nose can get ruffled by some of the strangest things. One false move may trigger an epic sneezing fit, and the 1969 978-day record is ripe for the taking.

Let's look deeper into your nose and all of its mysteries, shall we?

Sneezing is bad for the soul.

In 1515, Leonardo da Vinci dissected a human brain in an effort to find the soul. Though his soulsearching came up empty, this did not stop people from believing that the soul lives inside the head – a concept widely held during that time. When someone sneezed, the soul was believed to have been thrown from the body, thereby leaving it open for invasion by evil spirits.

Sneezing is good for the soul.

The good news is that once invaded, the body would try to quickly force the spirit out; this is best accomplished, of course, by sneezing. No matter which way the spirits are moving, however, sneezes were thought to be a gateway to the supernatural.

If you say "God Bless You," God might spare you. Or not.

The origin of this custom is varied, but one of the more prevalent theories is that during the 6th-century plague, which originated via disease-carrying mice in Egypt, Pope Gregory I urged divine intercession to help ward off illness. Because sneezing was one of the first signs of the deadly plague, he commanded people to say "God Bless You" after a sneeze. Even so, by the time the plague had run its course, it had killed half the population of Europe. Pope Gregory may have benefited from a backup plan.

Your heart stops or skips a beat when you sneeze.

It doesn't. However, the increase in pressure in the chest during the sneeze reduces blood flow into the heart from the veins, says Dr. Nancy Sweitzer, chief of cardiology at the University of Arizona's Sarver Heart Center. That leads to a weaker, less forceful beat, which can cause the sensation of a skipped beat.

"The heartbeat is determined by the electrical system of the heart, which is typically on autopilot and just keeps going," Sweitzer says. "The electrical activity of the heart is constant through a sneeze, but the mechanical 'pumping' may be reduced in force, particularly during a forceful sneeze."

The sneeze: once again proving that feelings are not facts.

Tweezing your eyebrows can make you sneeze.

Weird, but true. Those darn nasal nerves are so capricious. Even something as simple as plucking your eyebrows can irritate the nerve endings in your face, which in turn makes them fire a signal to hassle the nasal nerve. And when you irritate your nasal nerve, it irritates you right back – by making you sneeze.

"The eyebrows and the nose are both innervated by the same branch of the trigeminal nerve, which can be stimulated by tweezing the eyebrows," says Dr. Apple Bodemer, an assistant professor of dermatology at the University of Wisconsin. "The neuronal excitation from plucking can travel to the nose — resulting in a sneeze."

But take heart! You can enlist your eyebrows to fight back. "Putting pressure on the eyebrow while plucking can short circuit the response and block the sneeze," says Bodemer.

Sneezing always comes in threes.

First of all, if you sneeze three times it does not mean that someone is gossiping about you or that you're going to win the lottery. Save that stuff for the playground. Most people sneeze more than once because their first sneeze just didn't pack the punch needed to rid their nasal passages of all irritants. Whether that's three times or 10 times all depends on the power of your nose. The person in the next cubicle who sneezes 15 times in a row has truly wimpy sneezes. Sneezing once is something to brag about, maybe even put on your resume.

Bright light can make you sneeze.

This true phenomenon is called the photic sneeze reflex, and it affects up to 35 percent of the population. This sneeze tends to happen when suddenly moving from dim light to bright light, such as emerging from a movie theater or driving out of a tunnel. The photic sneeze reflex is thought to be genetic, but scientists are still puzzling over this one.

Satiation Brings On Snatiation (What?)

If you were born into a line of snatiators, then your genetically cursed family will have trouble talking over a big meal. That's because they'll be too busy sneezing as a result of their full stomachs. Scientists still don't fully understand the connection, but the neurons activated during digestion are perilously close to the sneezing neurons, and, well, you can glitch. Depending on who comes to Thanksgiving dinner, this can be a good or bad thing.

A study on snatiation found that the sneezing has no relation to what you're eating, and it occurs only when you are so full you can't possibly take another bite. Use this knowledge wisely.

Sneezing is "catching," like a yawn.

It is true that emotions can affect your nasal membranes. Fear makes them shrink (which can make you sneeze), and sadness makes them swell (which can also make you sneeze.) Though there is conflicting evidence, yawning has been linked to empathy, and one study showed that psychopaths — people who lack empathy — may even be immune to contagious yawning.

If sneezing fits are like yawning fits, does that mean that if we are tuned into others' emotions, we might sneeze out of sympathy? Though hard evidence is murky, there is some reason to believe that both yawning and sneezing fits may be powered by the mind, and some sneezing fits have been successfully treated through psychotherapy.

The definitive answer is "maybe."