When you're young and in elementary school, they usually have those nice asher yatzar signs on the wall right outside the bathroom. Lots of kids see these signs, though not that many actually recite what is written on them. They sort of end up blending into the wall as decoration.
At a certain point when you get older, though not even that much older, you suddenly realize how important that bracha is. The idea of a young person becoming ill is suddenly not a completely foreign concept. It's actually a very real, horribly frightening one.
Sometimes it's like there's this lack of control because no matter how well you take care of yourself, you are never completely immune to anything. I guess the safest way to take care of yourself is to turn to God. Imagine how unbelievable it is that we have the opportunity to keep on reminding God that if anything goes wrong with us, "Iy efshar l'hitkayem v'la'amod lifanecha." We won't be able to get up and stand before Him!
I know saying that doesn't make anything less scary, but I think the bracha itself is so vital to say. I used to always forget to say it but a few years ago, I started to and each time I say it, I feel an overwhelming thankfulness that I am currently healthy and functional.
There is so much out there that is frightening and terrible and too many of us know some of it too well. But we can't thank God enough for each healthy moment we have, because each second is a gift. We can't forget that.