Science has done it again. Dirty pigs are healthier pigs. It has been proven. Don’t ask how, because it involved a lot of fetal pigs (which makes my undergraduate pig dissecting PTSD flare up), poop and blood. But it also involved a lot of wallowing and I am ALL about science that proves that wallowing is good for you.
Sure, the title – Environmentally-acquired bacteria influence microbial diversity and natural innate immune responses at gut surfaces – scintillating as it is, might not immediately strike you as a defense of all that is good about being dirty. But pull up a chair and consider the dirty details.
Gut immunologists took baby pigs and sent them outside, inside or into a kind of antibiotic-laced biologic bubble. The guts of the outdoor, mud-wallowing pigs were full of healthier bacteria than the indoor pig guts. Not only was there more of the good stuff in outdoor beasts, there was also less harmful bacteria in the chute. Most cool and interesting, though, is that the bacterial composition of the piggies’ guts influenced the expression of immunologic genes: pristine, white-glove pork expressed more inflammatory genes and other icky inflammatory stuff.
I know what you’re thinking. Pigs aren’t human, Dr. Rentel. True. Based on this study I’m not going to build a heated pigsty with a giant HDTV for me and my kids in the backyard. There is, however, a growing, stinking, microbial-filled gooey heap of evidence that human interaction with bacteria is good. Why does the prevalence of autoimmune diseases and allergies keep going up? This study gives some very direct, powerful evidence as to how the cascade of autoimmune badness gets started. Okay, yes, in pigs, but pigs are a whole lot like us.
As my favorite infectious disease specialist in the whole wide world (Dr. George Gianakopoulos) used to say, “Nature abhors a vacuum. Kill the good bacteria and welcome in the bad.” I’m not saying you should order dirt for take-out tonight. But skipping the whole-body antimicrobial gel bath every day might not be a bad idea.
Victoria Rentel, MD (OSU Student Health Services Alum)
BMC Biology 2009, 7:79