Did you know that hydrogen sulfide, molecule for molecule, is as lethal as cyanide? The only difference is, one of them's in your farts (at far too low of a concentration to harm you, except psychologically).
Did you ever wonder if you could eat (or do drugs) with your butt?
Did you ever wonder what cat food tastes like? And why that should matter to humans? And why dogs (and rats, and others) eat their own poop?
And have you ever thought, really THOUGHT, about your own saliva?
I bet you're thinking about it now.
It's weird, isn't it.
But no saliva, no rectal storage, and no potentially lethal levels of hydrogen sulfide will stop the intrepid Mary Roach, as she embarks upon her latest book, Gulp: Adventures on the Alimentary Canal.
The digestive system, the alimentary canal, is something that is worth, well, ruminating on. When it comes down to it, as one of Roach's sources cheerfully states "We're basically a highly evolved earthworm surrounding the intestinal tract". We eat to live, but many of us also live to eat. So why, then, do so many aspects of the digestive system make us a little queasy? Spit. Vomit. Poop. We live with it all our lives, and when it's IN us, it's not so bad, but put it on the outside? EW.
But while the subject matter is a little gross, Roach's book is well worth getting over your own gastrointestinal reservations. It's a journey through the digestive system, from the taste and smell of what goes in (yes, that includes cat food, and there are human tasting panels for it), to how we might be able to to transplant what comes out. On the way, Roach visits salivary experts (they DO exist), people who do fecal transplants, a murderer in for life, Elvis' doctor, and one very, VERY large colon (with owner no longer attached). She even gives it up for science and gets a med-free colonoscopy (though details are, understandably, scarce, and really I don't think I want to know).
Roach does a fantastic job of conveying the interest and the wonder of the digestive system, from knowing just where your "self" extends when it comes to saliva (the tip of the tongue, but don't spit in your soup), to finding out just how much the rectum is capable of stretching (enough to get a magazine, eyeglasses, cigarettes, and a lighter. At the same time). While sure, some of the thoughts are a little foreign, Roach is able not only to gross out with the weird, but to put us in awe. It really is AMAZING that the rectum can hold so much. And it really is interesting how our view on spit changes entirely when it's no longer on the tip of your tongue. And when you think about your poop for long enough, you may think that you really could USE a Bristol Stool Chart.
A few of the chapters seem a little haphazard, as though they didn't really fit, but Roach couldn't let the story go (for example, the chapters on the human who lived with a fistula into his stomach and was the poor abused subject of a gastrointestinal research, though really interesting, doesn't seem to fit). And sadly, there's very little on the small intestine, possibly because there's not so much that's particularly gross or funny about it. Hey, the large intestine is just...well you can't SHOVE things in your small intestine, and dying of a puncture of the small intestine? Not nearly as weird as Defecation Induced Sudden Death.
But those aside, it's a fantastic journey through the nether regions, full of interesting and accessible examples of scientific inquiry, and the kind of stories that you're just dying to save for your next cocktail party (though I suppose it would have to be the right kind of cocktail party). It may well be Roach's most enjoyable book yet (though I have to say that Stiff holds a special place in my heart). It's definitely supplied me with a pile of great papers for Friday Weird Science, soon to be blogged for your enjoyment. Roach's voice is natural, curious, and full of a dry wit that keep you grinning, even when you're reading about whether or not a live slug could live in the stomach. She's just who I want to be when I grow up.
So check it out, pick it up. Maybe pack it away for some boring nights in solitary. Whatever floats your boat. And take an enjoyable ride along the alimentary canal.