Gross habit can ‘trigger brain inflammation that leads to Alzheimer’s’, scientists warn

THOUGH it's frowned upon in public, most of us will sometimes stick a finger up our nostril when we think nobody's looking.

However, this gross but seemingly harmless habit might have some unforeseen health consequences, with researchers claiming nose picking could increase your risk of Alzheimer's disease.

The theory behind it is that digging into your schnoz could allow bacteria, viruses and fungi to enter the brain, where it can cause inflammation.

As we age, this then damages brain cells and results in the symptoms we all associate with dementia.

There is a growing body of evidence linking the habit and unwanted outcome - and experts want even more research into the potential association.

Writing in the , last month, a group of scientists called for further studies to confirm these findings as data is "significant but scarce".

Citing 10 studies, they said: "Several pathogens, including those that invade the brain via the nasal epithelium, have been linked to Alzheimer's disease and have been isolated during post-mortem analysis.

"In conclusion, these studies show that nose-picking is a significant risk factor and has a part in the progression of Alzheimer's disease.

"We propose more investigation to understand the association of nose picking with Alzheimer's disease in the form of case-control studies with larger sample populations."

An Australian research team, whose work was published in , previously said that the brain-robbing disease responsible for memory loss and cognitive decline "is a complex neurodegenerative disorder" that can be caused by "many possible factors";.

But one of the key hallmarks of Alzheimer's is the buildup of two substances in the brain, amyloid and tau, which form plaques and tangles and impede brain function.

"More recent evidence suggests that neuroinflammation may also play an at least partial role in the development of the disease," the scientists said.

This refers to an inflammatory response in the brain triggered by injury or infection.

"Emerging research has explored the possible involvement of external, invading pathogens in starting or accelerating the neuroinflammatory processes in Alzheimer's disease," they added.

After completing a review of thousands of studies, they said the olfactory system - which includes the nasal cavity and nerve cells involved in our sense of smell - is "a plausible route" for pathogens to enter the brain.

Pathogens that might be linked to neuroinflammation include herpes, Covid-19 viruses, or bacteria that cause pneumonia or bronchitis, it is claimed.

Reflecting on the review's results, researchers suggested paying extra attention to hand washing as a potential way to dodge the disease.

Frequent hand washing and the use of hand sanitisers should be mandatory routine procedures for the incurable nose-picker

Researchers

"Among all the entry routes, the improvement of hand hygiene might be an easy prevention step, as learned from the Covid-19 epidemic," they said.

"One of the lessons learned from Covid-19 is the value of hand hygiene through frequent hand washing and the use of hand sanitisers, and we suggest these routine hygienic procedures be mandatory routine procedures for the incurable nose-picker."

However, the Western Sydney University team did question whether nose-picking was the cause of Alzheimer's, or whether the brain-robbing disease caused people to take up unhealthy habits leading to brain inflammation.

"One of the limitations of the 'infection hypothesis of Alzheimer's disease' is the debate of what comes first, the chicken (Alzheimer's) or the egg (infection)," the scientists said.

"Is it because subjects have a compromised immune system that they develop an infection leading to neuroinflammation and Alzheimer's?

"Or does increasing inflammation due to ageing and sub-clinical Alzheimer's disease cause immune defects or unhealthy habits allowing the entry of olfactory pathogens?"

Either way, their work adds to a list of studies suggesting a link between the two.

A Griffith University study carried out on mice found found a small link between the nasty habit and the build-up of proteins associated with the brain-robbing disease.

They ran tests on a bacteria called Chlamydia pneumoniae - a rare type of germ that can cause respiratory tract infections like pneumonia - and found evidence that routing around your nose could damage the protective internal tissues, making it easier for dangerous bacteria to reach your brain.

There are currently 900,000 people living with dementia in the UK. It is the UK's top killer.

Cases are on the rise with still no hope of a cure as current medications can only reduce symptoms.

Alzheimer's disease is a type of dementia that makes up the majority of cases, together with vascular dementia.