Scientists link nose picking to increased risk of developing Alzheimer's disease

Researchers from Griffith University in Australia have identified a plausible, albeit hypothetical, link between the common habit of nose picking and an increased risk of developing Alzheimer's disease.

The study, published in Scientific Reports, focuses on the bacterium Chlamydia pneumoniae, which is known to cause pneumonia and has been discovered in the majority of human brains affected by late-onset dementia.

The research demonstrated that when the nasal epithelium—the thin tissue lining the nasal cavity—is damaged, bacteria can travel up the olfactory nerve directly into the brain

 In mouse models, this infection occurred within a remarkably swift 24 to 72 hours. The brain responds to this bacterial presence by depositing amyloid-beta protein, a hallmark sign of Alzheimer's pathology.

Neuroscientist James St John noted the findings are "potentially scary for humans," as the evidence shows pathogens see the nose as a rapid route to the central nervous system.

"We're the first to show that Chlamydia pneumoniae can go directly up the nose and into the brain," St John stated, adding a professional "human touch" by advising against picking or plucking nose hairs to avoid damaging protective linings.

He warned that if the internal tissue is compromised, the number of bacteria reaching the brain could increase significantly.

While the current findings are based on animal models, the team plans to conduct human studies to confirm if the same pathway operates in people.

Future investigations will also determine whether the amyloid-beta deposits are a reversible immune response or a permanent precursor to neurodegeneration.