Gulp: Adventures on the Alimentary Canal is Mary Roach's fifth book covering some odd ball piece of science. It covers nearly everything from the nose, mouth and all the way through to the other end. The small intestine though gets pretty much passed over.
Roach's books are never just about how one part functions vs another part. No, instead, it's a collection of odd facts — or perhaps the most bizarre story she can find about that part or topic.
For the nose, we learn about fine art of wine and olive oil tasting (as its mostly done with the nose). I found her descriptions of trying to be a taster hilarious and reassuring. It's often assumed that anyone living so close Napa and Sonoma — major sources of California's wine and olive oil will be connoisseurs of one or both. That's not true and Mary proves that with her usual enthusiasm.
As the book progresses down the alimentary canal, the chapters go for more and more of the gross out factor. For the most part, Roach avoids sophomoric humor while talking frankly about what she's learned. Yet the writing remains entertaining.