Had my first at 29, history of colon cancer in the family and I had some GI issues, they did remove a cancerous polyp. Had one every six months for a while, then yearly, then every 3 years, now I am at every 5 years.
I think they need to do it younger than 45. I'd probably have stage 3 or stage 4 colon cancer now if they didn't find it 17 years ago. Friend of similar age lost his wife 18 months ago from colon cancer. My Boy Scout buddy was diagnosed with stage 4 colon cancer on Sept 1 of this year, he's one day older than me.