The science behind picking your nose – The Blueprint

Why do we do it, how can we stop it, and who else is at it?
Alice Cooke
Nose picking
The science behind picking your nose.

Interesting Engineering

  • Picking your nose could put you at risk of Alzheimer's and dementia
  • But we’re not the only ones at it, 11 other primates do the same thing
  • It can spread bacteria such as Staphylococcus, but might mean you have less dental cavities
The science behind picking your nose – The Blueprint
Nose picking

Interesting Engineering

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Last week, in a world-first, new research found that picking your nose could cause your eventual (albeit slow) demise. No, really.

Research published by Griffith University in Australia found that, in mice, bacteria can travel through the olfactory nerve in the nose and into the brain, where they create markers that are a tell-tale sign of Alzheimer's disease.

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Or, to put it more accurately, they found that Chlamydia pneumoniae uses the nerve extending between the nasal cavity and the brain as a direct path to reach the central nervous system. The cells in the brain then react by depositing amyloid beta protein, which is a key precursor to the development of Alzheimer's disease.

A study last year found that the leakage of a specific toxic compound in the bloodstream might be the fundamental cause of Alzheimer’s. The research team discovered that beta-amyloids form outside of the brain and are then pushed through the body's bloodstream via lipoproteins.

In mice, the researchers noticed that the olfactory nerve (also called the first cranial nerve) in the nose offers a short pathway to the brain, one which bypasses the blood-brain barrier. As such, viruses and bacteria can use it as a direct route to the brain.

Now, the team just needs to prove that the same pathway exists in humans and can be used in the same fashion by nefarious viruses and bacteria.

Pick your own

Nose-pickers of the world, be honest – has this put you off digging for gold? No, we thought not.

So, in the spirit of trying to put you off further (or maybe just provide you with some light entertainment while you claw away) we’ve put together a list of what we consider to be the most interesting scientific facts about picking your nose.

You absolute animal

First, let us take you to Madagascar (no, not to meet King Julian, stick with us, this is relevant.)

We’re there to talk about aye-ayes, which have been revealed to have some quite disturbing traits, according to new research published in the journal of Zoology and reported by The Guardian in the U.K.

You see, the animals have a very long middle finger that is used for tapping on hollow wood to locate grubs and fish them out. However, researchers have produced video footage of the same finger being used for nose-picking.

Why? Well, the researchers further note in their study that once the animal picks its nose, it follows up by licking the nasal mucus collected.

Dr. Anne-Claire Fabre, an assistant professor at the University of Berne and a scientific associate of London's Natural History Museum, who co-authored the research, said she was “really surprised” by the strange behavior she recorded.

She further explained that the whole middle finger disappeared up the creature's nose. “It is nearly 8cm – it is really long, and I was wondering where this finger is going,” she said.

The answer was… its brain.

The researchers created a 3D model using CT scans of the head and hand of the aye-aye and discovered that the digit extended deep into the head. Lovely.

And the aye aye isn’t alone. In fact, 11 other primate species, including capuchins, macaques, chimpanzees, and orangutans do it too. Some species go as far as using tools to do the job.

Why do we do it?

According to a 1995 study, 91 percent of people questioned reported that they pick their nose, and 75 percent said “everyone does it.”

Children pick their noses, this we know. But then children put their fingers everywhere – so I don’t think we need to delve too deeply into that.

As to why the rest of us like to have a quick delve, allergies and sinus infections can increase the amount of mucus and irritation in the nose, which can lead to the urge to pick.

And, in rare situations, nose-picking is recorded as being a compulsive, repetitive behavior. In fact, there’s even a condition linked to it. Rhinotillexomania is often related to stress or anxiety and is also associated with other delightful habits, including nail-biting and scratching. So maybe nose-picking can briefly ease anxiety?

Beyond that, structural irregularities in the nose have also been reported as causing problems that increase the likelihood of nose-picking. So there’s another possible excuse.

But surely we can agree that, in fact, most people pick their noses out of habit, rather than compulsion, a malformed nose, or a diagnosable condition?

So, how do you kick the habit?

Well, since you ask, Medical News Today has some handy suggestions.

These include (but are by no means limited to):

  • Mindfulness meditation, which can help reduce the stress and anxiety that can promote compulsive behaviors
  • Habit reversal training, which helps people become aware of and interrupt their habitual behaviors
  • Cognitive behavioral therapy, which helps people identify negative thinking and behavior patterns and develop more adaptive responses

So, if you’re struggling to give up searching for bats in the cave, we might just have come up with some answers for you.

The expert’s view

Back to Dr. Anne-Claire Fabre, of the afore-mentioned aye aye nose-picking research fame, to give us some sensible suggestions as to why we pick our noses.

“There is very little evidence about why we, and other animals, pick our noses. Nearly all the papers that you can find on the subject were written as jokes. Of the serious studies, there are a few in the field of psychology, but for biology there’s hardly anything.

She adds: “One study shows that picking your nose can spread bacteria such as Staphylococcus, while another shows that people who eat their own snot have fewer dental cavities.”

So maybe there are actually hidden benefits to picking your own?

We’ll leave it to you to be the judge – but at least now you can make a more informed decision about whether to pick, or not to pick. (Sorry Shakespeare – any resemblance to your work is entirely unintentional.)