Don’t you just hate that itchy, tickly feeling that creeps up the back of your throat and makes its way into your nose? Your nose twitches, you probably squeeze it to stem what’s about to happen. You might close your eyes and hold your breath, but often the ah-choo escapes quicker than you can react.
Sneezing. The body’s way of removing irritants from your nose or throat. An involuntary and powerful expulsion of air, and occasionally other less pleasant particles.
1. They travel… but now as fast as you think
Though there has been much discussion about just how fast a sneeze can travel (with claims it can move at speeds of up to 160km/h), there is nothing to prove sneezes achieving such a speed are true. The guys at Mythbusters, Jamie Hyneman and Adam Savage, tested their sneezing performance and came up with 63km/h and 56km/h respectively. While a team of scientists in Singapore found that sneezes can travel up to 16km/h.
2. You can’t sneeze in your sleep
When you lie down, the mucous membranes in your nose actually swell, which should make you more sensitive to dust particles being sucked into your nostrils. This puzzled scientists.
It turns out that during REM sleep — the deep and restful sleep you achieve when you are dreaming — all the muscles except those that control the eyes are essentially paralysed. This includes the muscle that expands and contracts to let your sneeze out.
3. Sneezing doesn’t make your heart skip a beat
However, it does slow your heart. Just a tad though. This might be due to both the deep breath you take before you sneeze, which tightens the muscles in your chest and increases pressure to your lungs, and the stimulation of the vagus nerve (that’s the long nerve that extends from the brain to the abdomen) that occurs during a sneeze.
4. Sex can trigger a sneeze
Believe it or not post-sex sneezing is quite common. While researchers aren’t entirely sure why it occurs, it could have something to do with the autonomic nervous system, which regulates things like heart rate, digestion and the tissues and fluids connected with arousal.
Also, the sun can trigger a sneeze. Sneezing as a result of being exposed to a bright light affects roughly one in four people. Scientists call this sneezing condition autosomal dominant compulsive helio-opthalmic outbursts of sneezing (ACHOO, did you see what we did there?) and it describes the occurrence of sneezing from looking at the sun or any bright light.
Oh, and if you happen to tweeze your eyebrows, it can cause a reaction that makes you sneeze too.
5. You definitely should cover your mouth
There’s a good reason you should cover your mouth when you cough or sneeze, and thanks to a study in New Zealand there is now proof that the little particles escaping from your sneeze include a lot of bacteria. Those particles also stay suspended in the air for longer than you realised.
6. It’s unlikely you could keep your eyes open (no matter how hard you try)
Do you remember that threat “You’re eyes will pop out if you sneeze with your eyes open”? No matter how hard you sneeze, your eyes are unlikely to come flying out of their sockets (the guys at Mythbusters tested it too). The reason we close our eyes when we sneeze is simple — it’s just a reflex. The nerves in your nose are connected to your eyes, so when you sneeze it causes you to blink.