"When it comes to literature about eating," author and anatomical explorer Mary Roach says, "science has been a little hard to hear amid the clamor of cuisine." Perhaps this is because we prefer to think about (and look at pretty pictures of) what we put in our mouths, rather than consider what happens after we start chewing.
The premise of Ms. Roach's latest book, "Gulp," seeks to make that science a little louder. "The human equipment," she claims, "and the delightful, unusual people who study it -- are at least as interesting as the photogenic arrangements we push through it."
"GULP: ADVENTURES ON THE ALIMENTARY CANAL"
By Mary Roach
W.W. Norton & Co. ($26.95).
If that sounds a little bit too icky for a spot of light reading, then consider the title (a monosyllable like its predecessors, "Stiff," "Bonk" and "Spook"), which not only describes the beginning of the journey the book takes through the alimentary canal, but -- gulp -- suggests the apprehension associated with it. It is witty, and wit is what lends Ms. Roach's work that special quality that makes difficult subjects not only palatable, but un-put-down-able.
Never before has the process of eating been so very interesting. Ms. Roach delivers the science behind processes we all know take place, but with a contextual framework that allows us to relate it to the world in which we live. The role that smell plays in stimulating the salivary glands and appetite is discussed by drawing our attention to the palatants, or additives, that pet food makers engineer to get Fido and Tinkerbelle to nosh down on all that dry kibble -- it's the same kind of tinkering that allows a potato chip to satisfy with "a tiny sonic boom inside your mouth" because humans like to eat crunchy things.
Ms. Roach is masterful at creating analogies that make sense. "Laundry detergent is essentially a digestive tract in a box. Ditto dishwashing detergent: protease and lipase eat the food your dinner guests didn't," she points out. She's just as adept at providing snippets of information you've always been curious about: "Morning breath" is hydrogen sulfide released by bacteria consuming shed tongue cells while you mouth-breathe for eight hours; saliva normally washes the debris away." Now you know.
Ms. Roach does not back off from the topic's rich font of scatological humor; she describes the possible effect of inadequate colonoscopy preparation (leaving pockets of highly flammable gases) as "an internal Hindenburg scenario." If there is the slightest hint of comedy in a name, she is sure to note it, such as when discussing this otherwise serious topic: "Hotdogs, grapes, and round candies take the top three slots in a list of killer foods published in the July 2008 issue of the International Journal of Pediatric Otorhinolaryngology, itself a calamitous mouthful."
Individuals and Institutes are not the only ones skewered -- sometimes she takes out whole countries; when, in 1831, the nutritive value of bouillon or broth was a question being asked by those charged with serving it to the poor, she quips "The French Academy of Sciences sprang into inaction, appointing a committee to look into it."
If you ever wondered whether it's possible to eat so much you burst (no -- well, maybe); or if you really need to chew your food before swallowing (yes and no); or whether you can die of constipation (no -- well, sometimes); then this is the book you should take with you into the bathroom to read. The bathroom is where we end up, of course, on this long journey, which is not coincidentally the venue of Elvis' death (from "fatal arrhythmia," we discover, probably brought on by "Valsalvic seesawing" -- read the book for a definition of that one).
Ms. Roach approaches her subject with the kind of glee associated with those whose professional lives have them arm-deep in places the sun don't shine, such as Dr. Khoruts, a specialist in colonic bacteria transplants, who enthuses, "We're basically a highly developed earthworm surrounding the intestinal tract," and that "people are surprised to learn: they are a big pipe with a little bit around it."
"Most of us pass our lives never once laying eyes on our organs, the most precious and amazing things we own. Until something goes wrong, we barely give them a thought," Ms. Roach says. After digesting her book, you cannot help but think about what that really means.
Micki Myers (mickimyers.com) is a writer living in Squirrel Hill. Her cancer memoir, "It's Probably Nothing ... (Or, How I Learned to Stop Worrying and Love My Implants)," will be published in October by Simon & Schuster.