I own several pairs of fit flops.  I actually prefer to not wear any other kind of shoe because these feel so good on my feet!  That is not always possible but I definitely feel the difference when I wear some other type.  I had a lot of feet, knee and back problems a couple of years ago.  I mainly wore athletic shoes with good support systems because of it but when I got up in the morning and walked down a flight of 4 stairs with my dogs, I would have to hold the rail and watch for my left knee to let go. I have fell before because of this knee collapsing under me with no warning.  I was walking in a department store one afternoon with a friend and my feet were hurting so bad that I had to sit down.  My friend brought me over a pair of fit flops to try.  I fell in love instantly!  Since that day, wearing fit flops has changed my life!  I have not had one case of collapsing knee since.  My feet don't hurt in the morning at all!  Never the case for many years before.  I am 58 years old, in good health other than this problem.  I'm writing this hoping that maybe this can help anyone with a better support system for their feet.  I have a large extended family and they are all wearing fit flops now with the same results so I know I'm not imagining the effects I have seen.  Buy as many as you can.  You won't be sorry.