Picking your nose can lead to Alzheimer's disease

 When a person picks his nose, he does not give the impression of an intellectual. But now scientists have found out that an apparently innocent activity can lead to the degeneration of the nervous system. At least in mice.

The corresponding study is published in the journal Scientific Reports.

In our nasal cavity is the olfactory nerve, which, as the name implies, is responsible for the perception of smell signals. However, this narrow flagellum of nerve cells hides an ominous secret: it connects the air in the nose to the brain directly, bypassing one of the body's most important defense systems — the blood-brain barrier, which prevents microbes and toxins from entering the bloodstream to the nervous system.

The olfactory nerve bypasses this barrier, directly "connecting" to the brain. As a result, both bacteria and viruses use such a "loophole" that is not controlled by the immune system. Scientists from Griffith University (Australia) proved that Chlamydophila pneumoniae, one of the main causes of pneumonia in humans, is able to reach the brain from the nasal cavity via the olfactory nerve and cause alarming changes in nerve cells.

Naturally, the invasion of the pathogen into the "holy of holies" of the body does not go away without a trace, and nerve cells immediately react by depositing beta-amyloids. Normally, these proteins are thought to be involved in the antimicrobial and antifungal defense of the nervous system, but in addition, their appearance in the brain is one of the hallmarks of developing Alzheimer's disease.

So far, the research has been conducted only on laboratory mice, but the results sound alarming for humans as well. In the future, the research team plans to test whether the bacteria, which is dangerous to health, can use the human olfactory nerve to penetrate our brain.

And what's the point of picking your nose? The fact is that unintentional damage to the delicate mucous membrane of the nose or pulling out hair can lead to an increase in the number of pathogenic bacteria that can reach the brain through the olfactory nerve.