Oh, unknowable universe, why you so crazy? Allow Techly to shine a light into the darkness by explaining why some people sneeze when they chew gum.
Firstly, what exactly is a sneeze and why do we do it? It does seem odd that our days are occasionally punctuated by the unstoppable urge to close our eyes, risk whiplash and spray everything in the room (that’s no exaggeration – check out this mathematical physicist’s slow-mo video).
According to the good people at National Geographic: “When we breathe in foreign particles, sensors in our noses and sinuses detect the objects. The sensors signal the cilia—tiny, hairlike paddles that line our nostrils and sinuses—to move to expel the irritants.”
Furthermore, a recent study published in the FASEB journal found that following a sneeze, the cilia are more highly active for a couple of minutes, essentially flushing the sinuses out and starting fresh.
So that makes sense in the case of dust and the like, but what about more abstract sneezes?
Things like sunlight for example, which has been confusing people for long enough that even famous Ancient Greek philosopher Aristotle found the time to weigh in by suggesting it had something to do with an increase in temperature (we actually got to the bottom of that one here).
Fast forward a couple of thousand years and French researcher Sedan found in the 1950s that some of his patients sneezed when first exposed to bright light such as his opthalmoscope and assumed he had happened across a rare condition. This came to be known as photic sneezing and continued to puzzle researchers, even though papers such as this one made note of certain aspects of the phenomenon, like the fact it seems to be a familial trait and, more oddly, “the percentage of photic sneeze is significantly lower in white females than in white males”.
Although that research focuses specifically on the link between optic stimulation and sneezing, the BBC’s report has a clue for our chewie purposes: “it could be the result of a process called ‘parasympathetic generalisation’. When a stimulus excites one part of the body’s parasympathetic nervous system, other parts of the system tend to become activated as well.”
So if that’s the case then what is the parasympathetic nervous system? As defined here by Medicinenet it is “the part of the involuntary nervous system that serves to slow the heart rate [and] increase intestinal and glandular activity.”
So, the question we need to answer is whether or not mint has an effect on the digestive system, which would, in turn, stimulate part of the parasympathetic nervous system and finally, as stated by the BBC, cause a reaction elsewhere in the same system, which includes the nose, and result in a sneeze. Phew.
Well, over to the University of Maryland Medical Centre then: “menthol and methyl salicylate, the main ingredients in peppermint, have antispasmodic effects, with calming effects on the gastrointestinal tract”.
(While that may not be the most scientific video, it is my strong belief that you should never pass up an opportunity to watch a small elephant sneeze.)