City People More Prone To Allergies, Too Germ-Free For Own Good

05/08/2012 2:30 PM |

Put down the hand sanitizer. It appears that Nietzsche and Kelly Clarkson may have had a point about that which doesn’t kill you making you stronger: Finnish researchers have found that lack of exposure to teeny-tiny bacteria in the “natural environment” makes city people more prone to allergies and asthma. Researchers argue that because our nebbish, indoor bodies aren’t exposed to a diversity of bacteria, they’re left defenseless for the spring onslaught of plant fumes.

The study, which was published in the Proceedings of the National Academy of Sciences, found that one class of bacteria in particular had an effect on stimulating immunological response (and therefore decreasing allergen sensitivity). The more gammaproteobacteria you’ve got living on your skin, the less likely you are to freak out in the presence of daffodils or floating cat hair. People who live on farms or near forests are exposed to gammaproteobacteria plenty, but city-dwellers are lacking.

“Urbanisation is a relatively recent phenomenon, and for most of our time we have been interacting in an area that resembles what we now call the natural environment,” [Dr. Hanski, co-author of the study] said.

“Urbanisation can be seen as a lost opportunity for many people to interact with the natural environment and its biodiversity, including the microbial communities.”

While it was not possible to reverse the global trend of urbanisation, he said that there were a number of options.

“Apart from reserving natural areas outside of urban areas, I think it is important to develop city planning that includes green spaces, green belts and green infrastructure,” Dr Hanski suggested. [BBC]

The BBC pointed out another recent study that highlights the effect lack of green space can have on urban populations. According to a study published in the journal Landscape and Urban Planning, urbanites who don’t have access to natural environments suffer higher stress levels, as measured by the amount of cortisol found in their saliva.

Prof Ward Thompson said that the study provided an objective measure of stress associated by the lack of green spaces in urban areas.

“We know that if you live near more green spaces, and you are from a deprived urban population, you are more likely to be healthier,” she observed. [BBC]

In conclusion, if you don’t want to be a snivelling, stressed-out blight on your social circle, it’s best to spend some time smelling the flowers. Bathe in some gammaproteobacteria, try developing new microbe relationships. Hell, why not eat a handful of dirt? Okay, perhaps that isn’t the best idea. Still, there’s no doubt that being overly hygienic has its downsides too—it’s time we learn how to stop worrying and love the bacteria.

[Via the BBC, Grist]