If you’re of a certain age, have inherited some particularly nasty genes, or are having gastrointestinal issues, your doctor will instruct you to have a colonoscopy. Don’t be blindsided by this backside-based inspection of your large intestine. These annals of my most recent colonoscopy will give you a heads up on the, er, down low.

One week before the colonoscopy: Meet the Gastroenterologist. Although pre-procedure meetings with doctors always feel like an insurance money-grab to me, I think this one is necessary. While I could have passed on the umpteenth review of my medical history —…