When I read Packing for Mars two years ago, I was very vocal about how my favorite chapter was her detailed exploration of pooping in outer space*, so it was with much excitement that I realized her next book, Gulp (subtitled Adventures on the Alimentary Canal) was about the science of eating, digesting, and yes, excreting. Maybe you think that's gross, and if so, to you I say THIS.
*Seriously, if you're not going to read the whole book, at least read that chapter. She includes a transcript where astronauts see one of their turds floating around, and they're all, 'It's not mine!' 'Mine was more gooey!' 'Mine looked like a snake!' or something like that. It's amazing.
I did indeed learn way more about pooping (and not pooping) in Gulp than I had bargained for. I also learned about saliva and parasites and exploding stomachs and how smelling is more important to eating than tasting and how Elvis was really killed by his colon (Roach has great personal interviews with experts that accompany each of these things, including one with Elvis' doctor). Also: how some people think the dragon myth was started because of cavemen kicking snake corpses close to a fire, which might have caused the explosion of other dead animals being digested inside the snake, releasing a gas that then burst into flames out of the snake's mouth (this was in one of the chapters about the science of farting -- yes there is more than one). Also also: poop transplants are a real thing.
Actually, I want to talk about that poop transplant thing some more because I think it's the perfect example of what Mary Roach is all about. Poop transplanting -- or as it's known in the medical community, fecal transplantation -- is actually a really beneficial procedure, although it sounds majorly disgusting. The human colon is a veritable colony of bacteria, most of it beneficial to our digestion and immune systems. When that balance is upset by something, like a large dose of antibiotics for example, or if a person is born without certain bacteria (fun fact: babies get most of their bacteria from their mother at birth) diseases or disorders can result. The example she uses is the common bacteria c. diff, which in the case of the patient she observes, has taken over his colon due to an absence of other more important bacterias. Poor guy's had basically nothing but diarrhea for YEARS. But after his fecal transplant? The proper ratio of bacteria is re-established and his digestive problems are cured in a matter of days.
And yet, as Roach is careful to note, the medical community does not take this procedure seriously, in large part due to the taboo surrounding its subject matter. No insurance company yet recognizes the treatment as valid, and it's extremely hard for doctors and scientists to get funding. Also a factor is that drug companies do not enjoy the idea of a procedure that does not involve drugs, and that in fact, removes the possibility entirely that drugs will be needed by patients in the future. But Mary Roach loves this stuff, the stuff nobody wants to think about, and she loves the people who spend their lives asking questions and doing weird experiments just like this one, because she understands that we need people like the guy who invented poop transplants to think outside the box. If they're not doing it, who the hell will?
I suppose it will be another two years before we get the next Mary Roach book, but I'm willing to wait if she's willing to keep writing books like this one.