Some people said what I had was a “real thing,” and that it even had a name: blood-injury phobia (see You Look a Little Pale,). Others just said I had a weak stomach. In biology lab, everyone around me wielded scalpels and seemed remarkably brave, while just I prayed for the bell to ring. I started to realize something funny, which was that hearing disturbing stories bothered me more than actually seeing something gross. It was my imagination, in the end, that really got the best of me.

      After a while, the other kids started to look out for me. They let the teacher know when a news topic of someone finding a severed hand in the woods or Ozzy Osbourne chewing the heads off bats came up that maybe they should change the subject—either that or give me a pass to study hall. They’d tell me not to look at a slide showing a giraffe carcass being torn apart by leopards. Sometimes they caught me in time, and I put my head between my knees before I blacked out. Most of the teachers understood. I learned to get used to spinning rooms. And to sit by the exit signs.

      Family members joked that after all that fainting, I’d grow up to be a surgeon. That didn’t happen. But I did grow up to write a book about blood, guts, gaping wounds, giant cockroaches, earthworm soup, flying mucus, belly lint, and dead bodies piling up on Mount Everest.

       So here’s the million-dollar question: Did I faint during the writing of this book?

      I did not—although that would have made for a good story. But the truth is, I finally outgrew the phobia when I realized that what actually made me faint wasn’t the sense of disgust or horror I felt when picturing the pile of severed limbs at Gettysburg—it was the fear that I would faint.

      Here’s what actually happened: You faint when your brain doesn’t get enough oxygen. For some people, a drop in blood pressure is the body’s natural response to seeing blood or, in my case, hearing about it. Scientists aren’t sure why, though some think that it may have once been adaptive, causing people to faint in battle or during an attack, to be passed over for dead by the enemy. The drop in blood pressure leads to light-headedness and, if it persists, to fainting, where you end up in a horizontal position and blood levels are restored to your brain. So basically, fainting is the body’s way of correcting the oxygen deficit to the brain. When you think of it that way, it’s not as scary as it seems—as long as you don’t bang your head too hard when you land.

      For me, fainting became a bad habit. When I heard about some guy getting a hole in his carotid artery, before I even had time to think about the blood spurting out, I started to panic about fainting. My blood pressure would drop, the room would spin, and away I’d go. It was a self-fulfilling prophecy. To train myself out of that cycle, I had to stop worrying that I would faint. Eventually I did. Now I don’t even have