Picking your nose while stuck in traffic might not be as harmless a habit as you think, a recent report has suggested.
A review of dozens of published studies into the mechanisms behind neurological diseases, compiled and written by researchers at Western Sydney University and published in the journal Biomolecules, collected strong evidence that people who frequently dig for gold are at a higher risk of developing Alzheimer’s disease.
“Neuroinflammation in Alzheimer’s disease might be partially caused by viral, bacterial and fungal pathogens entering the brain through the nose and the olfactory system,” the team wrote in the report.
Medically known as rhinotillexomania, chronic nose-picking introduces germs into the sensitive nasal cavity, leading to inflammation in the brain. Inflammation induced by such germs has been shown to cause a harmful build-up of amyloid beta proteins, a hallmark feature in the brains of people diagnosed with Alzheimer’s.
The neurodegenerative condition is the most common form of dementia, which research suggests more than 421,000 Australians – predominantly over the age of 65 – have, as of 2024.
Scientists are still unsure what exactly causes Alzheimer’s, but in the brains of patients they have observed a build-up of a protein called tau, which is associated with the body’s immune response. When immune cells are triggered by invasions too frequently, researchers believe that stress on the body, in the form of inflammation, can lead to various diseases.
“In recent years, emerging research has explored the possible involvement of external, invading pathogens in starting or accelerating the neuroinflammatory processes in AD,” the WSU team wrote.
“The olfactory system (sensory system used for smell) represents a plausible route for pathogen entry, given its direct anatomical connection to the brain and its involvement in the early stages of AD.”
Hands “contaminated with soil and faeces” may “accidentally expose” your olfactory system, and then your brain, to inflammation if you pick your nose.
An easy prevention step, then, is the improvement of hand hygiene, the researchers said, as learnt from the Covid-19 pandemic.
“One of the lessons learned from Covid-19 is the value of hand hygiene through frequent hand washing the use of sanitisers,” they wrote.
“We suggest these routine hygienic procedures be mandatory routine procedures for the incurable nose-picker.”