A recent study conducted by researchers at Griffith University in Australia suggests a potential connection between nose-picking and an increased risk of developing Alzheimer’s disease. Published in October 2022 in the journal Scientific Reports, the research indicates that nose-picking may allow certain bacteria to enter the brain, triggering responses that resemble early signs of Alzheimer’s.
The study focused on the bacterium Chlamydia pneumoniae, known to infect humans and cause pneumonia. Researchers found that this bacterium was present in a significant number of human brains affected by late-onset dementia. The study demonstrated that in mice, C. pneumoniae could travel through the olfactory nerve, which connects the nasal cavity to the brain. When the nasal epithelium, the thin tissue lining the nasal cavity, was damaged—potentially by nose-picking—the infection worsened. This led to an increase in deposits of amyloid-beta protein in the mouse brains, a hallmark of Alzheimer’s disease.
“We’re the first to show that Chlamydia pneumoniae can go directly up the nose and into the brain where it can set off pathologies that look like Alzheimer’s disease,” said James St John, a neuroscientist at Griffith University. He emphasized the rapidity of the infection, which occurred within 24 to 72 hours in the tested mice. This finding highlights the nose as a potential gateway for bacteria and viruses to reach the brain quickly.
While the implications of this study are significant, it is crucial to note that the research was conducted on mice, and further investigation in humans is necessary. “We need to do this study in humans and confirm whether the same pathway operates in the same way,” St John added. Despite the uncertainty regarding the effects in humans, the presence of similar bacteria in human populations warrants further exploration.
The study raises questions about the health impacts of common behaviors like nose-picking, a habit that, according to some estimates, affects up to 90% of people. St John cautioned against the practice, stating, “We don’t want to damage the inside of our nose, and picking and plucking can do that.” He warned that such damage could facilitate a greater influx of bacteria into the brain.
Future research will also seek to determine whether the increase in amyloid-beta protein deposits is a natural immune response that could potentially be reversed after the infection is treated. This line of inquiry is crucial, as understanding the role of bacterial infections in neurodegenerative diseases like Alzheimer’s could lead to new preventative strategies.
Alzheimer’s disease remains a complex and multifaceted condition. St John pointed out that while age is a significant risk factor, environmental exposures also play a critical role in its development. “Once you get over 65 years old, your risk factor goes right up, but we’re looking at other causes as well,” he explained.
The findings from Griffith University contribute to a growing body of research aimed at unraveling the mysteries of Alzheimer’s disease. As scientists continue to explore the complex interactions between bacteria and neurodegenerative conditions, the hope is that new insights will emerge, paving the way for effective prevention and treatment strategies.
