Study Suggests

Sometimes science makes discoveries that seem a bit, well, unexpected. Recent research has uncovered a curious and potentially alarming link between nose-picking and Alzheimer’s disease. While it might sound strange, a study involving mice suggests that nose-picking can introduce harmful bacteria into the brain, triggering conditions that resemble early signs of dementia.

The Study: Bacteria and the Brain

The team of researchers, led by scientists from Griffith University in Australia, focused on a specific type of bacteria, Chlamydia pneumoniae, which is known to cause pneumonia in humans. The bacteria were found in the majority of human brains affected by late-onset dementia. What’s more surprising is how these bacteria get into the brain—through the olfactory nerve, which connects the nasal cavity and the brain.

When the researchers damaged the thin tissue inside the noses of mice, the bacteria quickly made their way up the olfactory nerve and into the brain. The infected brains of the mice then began to produce more amyloid-beta protein, a key component of the plaques found in people with Alzheimer’s disease.

Nose Picking: More Than Just a Bad Habit?

The idea that nose-picking could introduce harmful bacteria into the brain has raised some eyebrows. While it’s important to note that this research was conducted on mice, the findings could still have serious implications for humans. Nose-picking, especially when it damages internal nasal tissues, might increase the risk of infections that could potentially lead to dementia.

The scientists were surprised by how quickly the bacteria took hold in the central nervous system of the mice—within 24 to 72 hours of entering the nasal cavity. “We’re the first to show that Chlamydia pneumoniae can go directly up the nose and into the brain,” said neuroscientist James St John, one of the study’s lead authors.

What Does This Mean for Humans?

Although more research is needed to confirm whether this pathway functions the same way in humans, these early findings are enough to give pause. Nose-picking, and even plucking nose hairs, could potentially damage the protective tissues in the nose and give bacteria a clearer path to the brain.

The research suggests that bacterial and viral infections might be critical factors in the development of Alzheimer’s. “It’s not just about age—it’s about environmental exposure as well,” says St John. As scientists continue to explore the complex causes of dementia, each new discovery gets us one step closer to finding ways to prevent and treat this debilitating disease.

Published in Scientific Reports, this study opens up a new avenue of investigation into how Alzheimer’s begins and what role bacteria play in its development.