WASHINGTON, Feb 6, (Agencies): New research has shed light on a surprising potential risk factor for Alzheimer's disease: picking your nose. The study suggests that this seemingly harmless habit could increase the likelihood of developing the debilitating condition.

Alzheimer's disease is characterized by progressive dementia, and one of its hallmarks is the presence of beta-amyloid protein in the brain. According to the study, beta-amyloid might actually be produced by the brain as a defense mechanism against pathogens that enter through the nasal cavity—such as those introduced by sticking dirty fingers in the nose.

The report, published in the peer-reviewed journal Biomolecules, proposes that the inflammation seen in Alzheimer's disease could be partly triggered by pathogens entering the brain via the olfactory system. Furthermore, there's evidence suggesting that beta-amyloid might act as a form of protection against microbial infections in the brain.

Various types of infections—viral, fungal, and bacterial—are linked to Alzheimer's disease. These pathogens can linger in peripheral tissues like the nasal epithelium for long periods without causing symptoms, eventually making their way into the brain and causing harm.

Explaining the connection, the report highlights the direct anatomical link between the olfactory system and the brain, suggesting it as a plausible pathway for pathogen entry, especially considering its involvement in the early stages of Alzheimer's disease.

Alzheimer's disease affects a significant portion of the elderly population in the United States, with over 6.5 million individuals aged 65 and older estimated to have the condition. Globally, it's the leading cause of dementia, affecting up to 70% of the 55 million people living with dementia worldwide. While age-related changes in the brain play a role, genetic, environmental, and lifestyle factors also contribute to the disease's development, according to the National Institute on Aging.