All I know is that I have been doing the raw food diet for one month now (after a two week cleanse) and I can't possibly imagine that something which has the positive effects I've been experiencing can be bad for you.
Since I began the fast and the raw food diet, I have lost 16 pounds. My skin is softer and more beautiful-- I actually look younger---IN LESS THAN ONE MONTH! My hair is way more manageable and my gray hair is going away. I haven't had to put hot packs on my tummy nearly as much---only when I have cheated.
Also, I remember reading somewhere that this oxalic acid scare was only pertinent to cooked spinach. Well, that's the part I remember anyway. That may or may not be true as is everything we read online or in any published manner.
I eat or drink at least six very large handfuls of spinach, kale and other greens a day. I have Fibromyalgia, so everything I used to put into my system would wreak havoc on me and remain in there for three to four days before coming through. I have not had that problem since I began the raw food diet. Not at all.
Maybe some people are allergic to greens and that is what causes them harm. No one should eat anything they are truly allergic to. That would be a real shame. I am so glad I am not. :)