Every single day, the human race produces around 70 billion farts - meaning roughly
10 of those are yours! But why doesn’t your gas seem half as smelly as those around you?
Why do we like the smell of our own farts?
Hilarious as it may seem, scientists have actually confirmed the fact that, in blind-smell
tests, we truly do find our own smells much more appealing than others. Simply put, the
more familiar you are with something, whether it be a song, picture or even a smell, the
more likely you are to prefer it. And because the bacterial population in your body producing
these smells is completely unique from every other individual, our farts truly have a one-of-a-kind
brand that your nose can differentiate.
But, from an evolutionary perspective, our reaction of disgust to other people’s odour
is likely our brains’ attempt to prevent us from doing harm to our own bodies; specifically
interacting with sources of disease. When you think of it, most things that don’t
smell good, aren’t good for you. And the greater the risk of disease, the more intense
your response will be.
Surprising as it may seem, farts can spread disease. In fact, there are many reported
cases of farts spreading Streptococcus pyogenes, a pathogen that can cause tonsillitis, scarlet
fever, heart disease and even flesh eating disease. Seriously, the pathogen is expelled
as fecal matter or poop particles in the air. Of course, this was a major concern for our
ancestors who ran around naked, but for us underwear or pant wearing folks, farts don’t
pose a real threat.
And it’s important that we’ve adapted to like our own odours, so that we can maintain
proper hygiene. In the same way, mothers perceive their biological children’s poop as less
offensive than others, which allows them to take care of them without disgust.
Of course, some of you may be thinking “I don’t find farts disgusting at all” - and
you’re not alone. Perception of disgust is a combination of variables like age, gender,
culture and even personality. So much so, that people who are more anxious or socially
conservative are often more sensitive to stink than their adventure seeking friends.
The anterior cingulate cortex, which processes surprise, also plays a big role. When we fart
we know it, and can anticipate the accompanying smell. But when somebody rips a silent but
deadly fart into a crowded room, the brains expectations of reality are smashed by the
negative stimulus, making it all seem even more foul. So next time you feel a silent
stinker coming on, you might want to give everyone a heads up. Unless of course, you’re
alone; then you can bask in the glory of your own stench.
Don’t forget, The AsapSCIENCE book just went on presale! Not only can you own a physical
version of some of your favourite video episodes, which we’ve re-drawn and updated, but we
wrote a whole bunch of new chapters answering questions that have never been answered here
on AsapSCIENCE! Check out asapscience.com/book to get your copy! We truly appreciate all
of your support!
You can also watch our latest AsapTHOUGHT video “The Science of Beards” where we
debate the scientific advantages of growing it out or staying clean shaven. To beard or
not to beard? Head over there with the link in the description, and let us know which
side wins!
And subscribe, for more weekly science videos!