Too Much Spinach?

I've been stuffing raw spinach into my juicer lately and today wondered how that will affect me.  Apparently, spinach (like many other leafy veggies and some fruit) contains oxalic acid.  Which, if your family history makes you prone to kidney stones, you'd be wise to avoid overdosing.

However, one source says that oxalic acid only becomes harmful when spinach is cooked.  The oxalic acid in raw spinach is not harmful.

But most intriguing is the percentage that spinach is protein.  Thirty percent!  When it tastes so good mixed with celery, tomato and carrots...why not continue throwing a handful in your daily juice?

Why the worried look?  Green stuff is good!

There now.  You see?

Juice this:
1 1/2 c. raw spinach
1 large carrot
2 stalks celery
2 apples
1 pear