First of all welcome to the area!
I had a rare intestinal 'thingy' a few years back from a hobby of building wooden boats.
Long story, but in the hospital for three days I read a book someone gave me called "The Maker's Diet" by Jordan S. Rubin.
This book was life-changing for me.
Although it is written by a Christian, you certainly do not need to be of that faith or any other to enjoy the wealth of information contained within. Just from changing my diet and exercising a bit, I have never felt better or had more energy in my life. And no I am not eating soy burgers and drinking green tea all the time.
And you are correct that the American healthcare system's mantra is to treat the illness, versus focusing on prevention and promoting a healthy lifestyle.
But that would not be very profitable, now would it?