It’s common and accepted wisdom that riding the subway, the bus, or (god forbid) an airplane is an inherently dirty experience. Surrounded in an enclosed space with a bunch of strangers who may or may not have the same standards of cleanliness you do. Rubbing up against you, breathing around you, coughing in the same airspace as you, maybe even touching your stuff. Personally, I get a bit twitchy just contemplating it.
Recently published research indicates that all that paranoia is justified to a much more intimate degree than even the most vigilant germaphobe ever considered. GI tract microbes, gut flora, the bacteria reproducing in your intestines at this very moment, call’em what you like. You, and everyone near you on the public transit means of your choosing, are likely sharing those little guys. Right now. Right this very instant.
Andrew Moeller, an evolutionary biologist from the University of California co-authored and published a paper asserting just that. His research has found that most social interactions result in a tiny bit of gut microbes being shared between individuals and groups. In our ever connected world of mass transit that means that inside your GI tract at this very moment are likely a tiny population of microbes from virtually every other part of the world. Your insides are likely way more cosmopolitan than you are.
Research conducted using chimpanzees over the course of 8 years seems to confirm this theory. The general conclusion the researchers came to was that the chimps belly bacteria was more similar the more social they were with each other. If the chimps were anti-social, like one tends to be after a night of banana daiquiris and picking parasites off of your partner, then their gastrointestinal microbiomes tended to be less similar. Family lines seemed to play no real part in the make-up, social interaction of any sort seems to be the major factor.
The chimps displayed a much more significant diversity than humans do in similar social situations. This is most likely because chimps, usually, live in environments and situations where they have a lot more contact with fecal matter than the average humans. The wonders of indoor plumbing are seemingly never ending.
Despite the general creepiness of this subject, perhaps even going so far as to be “icky”, one should be grateful for all this bacterial swapping. Your little gut buddies are usually working overtime to help fight off everything from diarrhea to colon cancer. Asthma, diabetes, reducing the risk of allergies, normalizing weight, all these things (and more!) your lovely gut flora play a part in helping with.
Keep that in mind and get out of the house more. Travel, meet people, make friends, put their hands in your mouth, whatever it takes to increase the diversity of your intestinal bacteria communities. Show them some love. Those little things are clearly important.