If you were to hear someone say "by making our world more sterile, we're actually making ourselves sicker," you might think they were full of it: initially, it sure doesn't sound like it makes any sense. Interestingly, however, it seems as if this may, in fact, be true: our attempts to make our world a cleaner place, we are slowly and steadily weakening our own immune systems!
It all started yesterday as I was working at the Morrison Natural History Museum, watering and destroying the angiosperms from the Jurassic Garden with "extreme prejudice," as angiosperms do not appear to have inhabited Colorado during the Jurassic Period. I started wondering why there was so much dead plant material around the base of the plants in the garden, and, for lack of a better conclusion, decided that it was probably because the bacteria that would normally digest these plants didn't actually live here. (I still don't know whether that is true or not). The topic of bacteria triggered my brain to start thinking about digestive bacteria: I was quite hungry, you see. It had been brought to my attention in the past that, even if humans were somehow able to miraculously clone a dinosaur, we almost certainly couldn't keep them alive. Each animal on the planet has its own, unique set of bacteria that helps it to digest its food. With the extinction of the dinosaurs, it is almost certain that the bacteria that constantly accompanied them in their digest tracts went extinct, as well.
This line of thought made me think about the passing of bacteria from the parents to their offspring. How is it done? I assumed that they weren't born with it, but I wasn't sure. I ended up thinking that perhaps, in animals that regurgitate food into the mouths of their young (like penguins), perhaps this was how the bacteria was passed. With perfect timing, out came Matt Mossbrucker, the director and curator at the Morrison Museum. I asked him whether it was, indeed, regurgitation that passed the bacteria on, and he said yes: partially. You know how many animals (such as your dog and cat at home) will eat poop? That's at least part of the reason: they're trying to get bacteria from the poop to help them digest their food!
After thinking about it for a few seconds, I realized that humans (most of us, anyways) neither regurgitate our food for our young 'uns, nor do we eat each others poop. So I asked Matt whether humans get this bacteria through breast milk: turns out, we don't. So how do we get the bacteria?
According to recent research, humans aren't getting enough bacteria to digest their food. Much of this research seems to indicate that perhaps this is the reason why so many humans have digestive issues, allergies, and the like. Matt also said that, just like I said in the introduction, "by making our world more sterile, we're actually making ourselves sicker." Still sound paradoxical? Well, ultimately, humans are trying so dang hard to sterilize their world with hand sanitizer, bleach, alcohol, and soap, that we aren't being exposed to as many pathogens. While in some cases this is a good thing, in other cases, our immune systems, just like the six-pack of someone who doesn't exercise, slowly weaken. And, of course, a weak immune system is good for no one!
So is the moral of the story to stop washing your hands? No, of course not. It's to go out there and eat poop. See you later, everyone!