Study Shows Picking Your Nose Could Hurt Your Brain. (Really.)

How often have you reminded your toddler to keep their finger out of their nose? Nose picking is generally seen as a harmless thing people do. Is it gross? Sure. But that’s the end of it, right? Not exactly. According to a new study, picking your nose could actually hurt your brain.

No, you’re not going to accidentally poke your brain while picking boogers. But you could introduce harmful bacteria to the nose, giving it easy access to the body’s control center, according to the new study, which was conducted in mice and published in Nature Scientific Reports.

Specifically, damage to the nasal mucosa may make it easier for a bacterium called Chlamydia pneumoniae to enter the brain. Infection with this bacteria has been linked to an increased risk of developing Alzheimer’s disease and dementia, according to supervising author of the study, Prof. James St John, head of the Clem Jones Centre for Neurobiology and Stem Cell Research at Griffith University in Brisbane, Australia.

The study shows that Chlamydia pneumoniae can enter the brain through the olfactory nerve, which is in the nose and has direct path to the brain. When the nasal mucosa is damaged (which can happen with excessive nose picking), it increases the risk of that olfactory nerve being exposed, opening the opportunity for this bacterium to enter the brain.

As Medical News Today notes, once the bacterium enters the brain, it can “stimulate the deposition of amyloid beta protein, potentially leading to the development of Alzheimer’s disease.”

“Other studies have shown that Chlamydia pneumoniae is present in Alzheimer’s plaques in human (using post-mortem analyses),” St John noted. “However, it is not known how the bacteria get there, and whether they cause AD pathologies or are just associated with it.”

It’s important to note that this study was done in mice, so the researchers also can’t be sure how the findings apply to humans, although studies in people are underway. The scientists are currently investigating whether there is a causal relationship between nose-picking and other health risks, including damaging structures and tissue inside the nose and spreading bacteria and viruses from the nose to surfaces.

So, if you find yourself nagging your toddler to keep their finger out of their nose, it might be a hill you want to die on.