Conventional medical wisdom is that everyone over age 50 should have a colorectal exam every ten years.
This is because polyps can be found and removed before they are cancerous, and even if cancerous, the disease is very treatable in its early stages. See, for instance:
Here is an interesting guy who says the dangers of such an exam outweigh the benefits. He also seems to think that fiber is bad for you. Is he just trying to scare you into buying his book?
And now back to the fluff: