> even though it’s a relatively benign procedure.

Not completely. Every once in a while they accidentally puncture the intestine with the probes and that becomes a significant medial problem. It doesn't happen often, but that is still a risk that doctors need to consider. If you are over 50 getting one every 10 years is a good idea, and there is some consideration if younger might be worth it. However so few people get colon cancer under 40 that it isn't worth the risks for most - but if there are other signs of a problem (either family history or symptoms) that changes things and it may be worth it.

I was diagnosed at 35 seven years ago with no history. Getting a colonoscopy never crossed my mind, much less being suggested by my general practitioner.

The trigger for me was blood in my stool. It was the slightest amount but I pursued it because that didn’t seem right. Turns out I had hemorrhoids which brought up something I feel hits others - I was embarrassed.

Fortunately the doctor that performed a banding procedure pushed me to get a colonoscopy purely out of being through and seeing the number of incidences increase at my age range.

I often wonder how much the embarrassment factor comes into play here.

For a screening procedure recommended as a mass conducted preventative measure in otherwise healthy people, harms must be regulated to a better standard than "doesn't happen often". The study that I read of was about serious issue occuring something like one in 120 procedures. It was done at Kaiser. Next time you're enjoying a sausage, take a moment to look at the sausage skins. If I understand correctly, our intestinal walls are quite thin, and even the colon vulnerable.