alt Hacker NewsYou're on a discussion forum where the topic is colon cancer. Surely you understand that people are going to discuss it?
It's a bit hard to tell from your post what you're saying. Certainly I can imagine being annoyed by constantly being given health advice from layman. But this is... a forum.
There's a bazillion ways to discuss a topic that don't involve giving advice with unearned confidence. Even just saying "My experience is that doing X helped" instead of "You should do X" is a massive massive difference.