John O'Connor
John O’Connor

We now share the planet with six billion of our fellow Earthlings. And we’re spread across roughly 200 nations.

For those of us fortunate enough to be at or near the top, life is quite good. We have inherited many perks and advantages that billions of others can only dream about. These include relatively better sanitation, healthcare, educational opportunities, food and drinking water — just to name a few of the big-ticket items.

But we are paying a price late in life for these First World trappings. For it appears that we are also inheriting a greater risk for Alzheimer’s disease.

People in more advanced nations tend to have far less contact with bacteria and viruses. While that’s a potentially good thing in many ways, it also raises problems developing immunity.

Researchers at Cambridge University wanted to determine whether this “hygiene hypothesis” could withstand a good scrubbing. So they crunched the numbers from nearly 200 countries.

Their findings: In nations where citizens aren’t exposed to as many dangerous microbes, the number of people with the dementia-inducing disease increases. In other words, less-stressed immune systems lead to greater risk of Alzheimer’s in later years.

For instance, areas with clean drinking water, such as the United Kingdom and France, have a 9% higher Alzheimer’s rate than countries where fewer than half the people have clean water access, such as Kenya and Cambodia. Full findings appear in the journal Evolution, Medicine, and Public Health.

Some experts say that while the study is interesting, it does not automatically cancel out lifestyle factors such as diet, education, and overall health.

It has been said that clean living is its own reward. But it also appears there are sound clinical reasons for dishing the dirt.