Is There A Connection Between Hygiene And Alzheimer’s?

Cambridge University has released the results of a study that indicate that high-income urban areas, located in industrialized countries with excellent sanitation and hygiene standards, appear to have higher rates of Alzheimer’s disease. In addition, countries in which clean drinking water is plentiful and easy to access have rates of Alzheimer’s at nine percent above the average. Health experts state that while the study is of interest, it does not consider other factors such as education, dietary habits or total state of health.

Hypothesis of Hygiene

The Cambridge study appears to support a hygiene hypothesis, which suggests that some aspects of modern living, like clean drinking water and antibiotics, contribute to a weaker immune system because of reduced exposure to viruses and bacteria. Lowered exposure means the body produces fewer T-cells to defend itself, and inflamed T-cells are a hallmark of Alzheimer’s. A researcher who worked on the study, Molly Fox, stated in a press release that there is an established relationship between living in a cleaner environment and an elevated risk of autoimmune disease and allergies, and now Alzheimer’s can be added to that list.

Overuse of Antibiotics

Another critical factor working against proper immune function is the overuse of antibiotic medications. Although they are considered a marvel of modern medicine, they are often prescribed to people who are sick with viruses, such as a cold or the flu. Since antibiotics only work on bacteria, using them in these instances lowers a body’s immune response while doing nothing to fight the virus that is causing the illness. Misuse of antibiotics has also led to a rise in resistant bacteria strains that are causing very serious health problems worldwide.

Study Results

The study used data from 192 different countries. Overall, those with better sanitation practices had higher rates of Alzheimer’s disease. Urbanized countries, where more than 75 percent of the population was located in cities, had a rate of Alzheimer’s that was 10 percent higher than non-urbanized countries. Aside from urbanization and sanitation, the levels of infectious disease in each country were taken into consideration and found to account for 28 to 33 percent of the discrepancy in the Alzheimer’s rate. Fox says that gaining a clearer understanding of the relationship between sanitation and Alzheimer’s will lead to better strategies to fight the disease in those who are vulnerable to it.

Other Considerations

A leader at the United Kingdom’s Alzheimer’s Research, Simon Ridley, stated he found the study to be intriguing, but that it does not prove there is a link between Alzheimer’s disease and higher levels of hygiene. He thinks the rate of Alzheimer’s is determined from a combination of lifestyle and environmental aspects, and the study did not explore other reasons that may contribute to the disease rate. Continuing research is needed into all the known factors that affect the risk of developing Alzheimer’s disease. While there is no way yet to prevent it, following a healthy routine of exercise and proper diet, along with monitoring cholesterol and blood pressure, are good ways to reduce the risk of Alzheimers.

While there is no definitive connection between better hygiene and sanitation standards and Alzheimer’s, the Cambridge study opens the door to further thought and investigation down the road.

Jody Moore is a science professor with over 16 years of teaching experience. Jody recommends reading more of her articles by visiting