Mary Roach is no stranger to the strange. She's chronicled the bizarre lives of dead bodies in Stiff and the wonders of sex in Bonk. In Gulp, she roots around the bowels of research literature for another topic that's difficult to swallow: the alimentary canal. Following food from ingress to egress, with a few way stations in between, Roach unearths innumerable fascinating factoids about colons, constipation, and intestinal parasites. As usual, she gold-pans through medical journals and interviews the folks for whom her subject is a lifelong obsession like the Italian woman dedicated to improving the reputation of saliva and the lab rat who's published 34 papers on flatulence. Some of her firsthand research is even hand-first, as when she plunges armpit-deep into the bored-open stomach of a live cow. Now, that's dedication.
All the science in Gulp, like much of what it focuses on, is fully digested. Roach switches easily between sometimes squirm-inducing technical terms like brachioproctic Google at your own risk and more colloquial phrasing like milk being ''horked out'' the nose, and her sense of humor occupies a space between deadpan and sophomoric: A footnote riff on the oft-confused Latin phrases per annum, meaning ''yearly,'' and per anum, meaning ''by way of the anus,'' is a perfect mingling of high- and lowbrow. As with Roach's whole body of work, Gulp is as engrossing as it is gross. A-5 Things We Learned From Mary Roach Books Stiff (2003)
Cadavers were crucified in a Paris laboratory to bolster the case for the Shroud of Turin's authenticity.Spook (2005)
An Oregon man built a device in his barn and killed eight sheep, three lambs, and a goat to try to weigh their souls.Bonk (2008)
An Egyptian study found that rats engage in less sexual activity when dressed in polyester pants.Packing For Mars (2010)
NASA can recycle and purify urine for space travel so it's ''clear and sweet,'' like Karo syrup.Gulp (2013)
Elvis Presley suffered from a ''megacolon,'' which contributed to his infamous demise.