I gained a lot of weight about 15-20 years ago, and at some point - I don't recall when- my belly button became an outie. Sometimes it goes soft on its own, but for the most part it is solid. Nothing extreme, but definitely noticeable.
Well, I was told by someone that it was a hernia. Ok. I thought hernias were painful and had noticeable side effects. I feel no pain To be honest, it has been purely a visual issue.
I've had this for at least nine to ten years, but I'm certain it was longer. I simply thought it was my belly button protruding simply because I had gained so much weight. It being a hernia never crossed my mind.