For a woman who’s just written a book about the human digestive system, Mary Roach is surprisingly cheerful.
The acclaimed Bay Area science writer seems perfectly happy to wade into subjects that would make most of us say “ick.”
In her new book, “Gulp: Adventures Along the Alimentary Canal,” Roach delves deeply into how we eat — and what happens after.
Informative and often hilariously funny, the book combines history, weird facts and up-to-the-minute interviews with physicians, researchers and other experts about events no one discusses in polite company.
Along the way, she covers chewing (how much is enough?), saliva (why do babies drool?) and flatulence (don’t ask). She visits hospitals, prisons and oral processing labs; witnesses a fecal transplant; and talks to Elvis Presley’s doctor about what really killed the superstar singer.
Roach, who is making several Bay Area appearances this week, is an avid researcher who pores over medical journals and websites and is willing to go just about anywhere to learn about her subjects.
“I spend a lot of my time making a pest of myself,” she says.
Working on the book, Roach was endlessly surprised — “the lining of your stomach blushes when you blush” — and often awed by what she learned.
“I realized that you can think of the entire alimentary canal as a tube that’s considered part of the outside of your body,” she says. “It’s like a doughnut hole — a tunnel through you that isn’t really you.”
Roach is aware that she goes to places that people might not want to think about. In four previous books, including “Bonk” and “Stiff,” she’s explored topics from sexuality to cadavers.
Yet her enthusiasm and humorous approach keep people reading.
“There’s an assumption that science is going to be a grind, and I think that can scare people off,” she says. “But you don’t have to go too deep to get a basic understanding of how things work. I don’t understand how that can’t be interesting to people.”
“Gulp,” she notes, was inspired by a conversation she had with a retired doctor. He was talking with reverence about digestive organs — “how nobody respects their innards, particularly below the belly button,” Roach says.
“It was a little gross and off-putting — and it just seemed to have my name stamped all over it.”
Mary Roach in conversation with Jack Boulware