Let’s start with the basics: what happens when you sneeze, and why do you do it in the first place? In the simplest terms, sneezing is your body’s way of clearing your nose of irritants and pollutants. During the course of an average day, you’re exposed to a range of environmental elements like dust and smoke. Sneezing is one of your first lines of defense against these potentially harmful contaminants.
One of the functions of your nose is to purify the air of dirt and bacteria before it makes its way further into your body. Most of these contaminants become trapped in the mucus inside your nose and are then neutralized by being digested in the stomach.
The inside of your nose is lined with a sensitive mucous membrane and tiny hairs that become irritated when you inhale perfume, smoke, dust, mold, or bacteria and viruses. This irritation sets off a series of events that eventually lead to a sneeze. Nerves in the nose immediately send an electrical signal to the medulla at the base of the brain, telling it that a sneeze is needed to clear the nose of pollutants.
Over the course of the next few seconds, a number of actions occur that prepare your body for the sneeze that is to come: your eyes close, your tongue moves to the roof of the mouth, and skeletal muscle in your body readies itself for the movements of the sneeze. And all this buildup results in the explosive force of a sneeze that you’re so familiar with.
During a sneeze, water, mucus, and air are expelled from your nose at great speed, possibly alongside microbes that spread disease from person to person. This is the reason that it’s generally a good idea to limit your contact with other people during the infective period of illness.
Even if this can’t be avoided, it’s important (and good manners) to cover your nose while you sneeze to minimize the chance of spraying others! If you use the inside of your elbow to cover your nose instead of your hand, you’ll also reduce the risk of spreading germs during handshakes.
Sneezing is an involuntary reflex — even though you can sometimes restrain a sneeze before it progresses, you can’t control it in the same way as actions like turning your head or moving your limbs. This is why sneezing can happen suddenly and without warning.
Here’s one last function that medical experts now know is served by sneezing. Academic studies conducted at the University of Pennsylvania suggest that sneezing is your nose’s way of ‘resetting’ the tiny hairs, or cilia, that line your nasal cavity. So whenever you sneeze, your respiratory system is rebooting itself in preparation for the next time it needs to expel any foreign contaminants or irritants.
Now you know why you sneeze and what happens when you do, but what about those myths and rumors…? Here is a couple of the most common:
Some myths contain a little grain of truth, and this seems to be the case here. As you’ll know from experience, it’s common to involuntarily take a deep breath immediately before you sneeze. This has the effect of increasing pressure in the chest and, consequently, reducing blood flow in the heart — resulting in lower blood pressure and raised heart rate.
As you breathe out, the opposite occurs: your blood pressure increases and your heart rate reduces. Sneezing also stimulates the vagus nerve, which extends from the brain to the abdomen and causes the heart rate to reduce. These combined effects can result in the heart slowing down, missing a beat, or even stopping briefly.
As troubling as the idea of your heart stopping may be, this is nothing to worry about — the interruption to normal activity in the heart is brief and quickly resolves itself in the vast majority of cases.
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Though this myth has little truth to it, many people believe that you can’t sneeze with your eyes open — or that some terrible catastrophe will result if you do. So here’s a simple truth: while it’s not impossible to keep your eyes open while sneezing, it’s extremely difficult. If you manage to do it, rest assured that your eyes won’t pop out of your head (another popular rumor!).
Here are a few surprising facts about sneezing:
- To medical professionals, sneezing is known as ‘sternutation.’ Try slipping that into the conversation the next chance you get!
- There are cases of people rupturing the tissue at the back of their throats by closing their nose and mouth during a sneeze. It’s a painful condition and, in rare cases, can require hospitalization. Remember that the next time you’re tempted to hold a sneeze in!
- Doctors report that a small percentage of the population can experience sneezing fits as a result of orgasm, or even sexual thoughts. While it’s not common, cases have been reported since the nineteenth century.