A new study published this week seems to suggest that good health hygiene which means avoiding germs is linked with a higher risk of Alzheimer’s disease (AD) and dementia. Put more ironically, living in a wealthy, developed, first-world country and being exposed to fewer bacteria and viruses appears to raise your risk of Alzheimer’s. It has found that high-income, highly industrialized countries with large urban areas and better hygiene and sanitation have much higher rates of Alzheimer’s disease.
The study, published in Evolution, Medicine, and Public Health found that industrialized countries with better sanitation and water quality had significantly higher rates of Alzheimer’s and Dementia than poorer countries where germs run rampant.
Is this theory true?
The latest study adds further weight to the “hygiene hypothesis.” This theory suggests that certain aspects of modern life, such as antibiotics and clean drinking water, are linked with less exposure to a range of bacteria, viruses, and other microorganisms. This lack of exposure might cause the immune system to develop poorly. Part of the immune system is a type of white blood cell, called a T-cell that defends the body against infection. T-cell deficiency has links to the types of inflammation commonly found in the brains of people with Alzheimer’s disease.
In the past, the “hygiene hypothesis” has been studied in relation to allergies, asthma, and autoimmune conditions. But right now, it’s just a theory and a theory with plenty of opponents. Alternative explanations for the data suggest that pollution, wheat allergies, and other byproducts of urbanization may explain the higher rates of asthma, allergies, and other diseases.
If you are one of those whose kitchens and bathrooms are awash in antibacterial products, and who carries hand sanitizer everywhere you go, it might be time to back off. Research has linked overuse of these products with higher rates of immune-associated disease, while other studies have shown that people who don’t use such products have stronger immune systems and less allergic sensitivity.
Using data from 192 countries, the researchers found that those with higher levels of sanitation had higher rates of Alzheimer’s. More urbanized countries had higher rates of Alzheimer’s, independent of life expectancy. Countries where more than three-quarters of the population were located in urban areas had 10% higher rates of Alzheimer’s compared to countries where less than one-tenth of people lived in urban areas.