Non-invasive screening is preferred at that age if one is low risk - a colonoscopy is not without certain hazards (I've had a handful of patients who've been perfed during routine scopes through the years; it's not common, but it's pretty catastrophic when it happens.) For those who are high risk, colonoscopy is recommended starting at 40; some sources say 35, depending (due to family history, my two youngest siblings were recommended to start at that age.)
For myself, I don't. When I'm listening to a book, I'm usually doing something else at the same time, so it's not getting my full attention. I don't think it counts as really reading it unless one is fully engaged.