EW, I read that a few days ago, must've been where they got the info for the Oprah show.
I think it's one of those things like BMI, where they define "normal" based on a median of a population that's overall pretty unhealthy. I know when I'm eating healthy (most of my calories from vegetables) I usually have a BM three times a day. And yeah. Exercise. Peristalsis only does so much (particularly if someone's eating a low fiber diet that takes a lot of muscular energy to propel). A lot of moving stuff through the bowels comes from external stimulation by body movement.
Speed comes from what you put behind you. - Judi Ketteler