It needs to be cooked and drained because of the high level of oxalic acid in it.
Oxalic acid needs to bind with calcium to be excreted, so not good for old bones.
I eat it, I steam it and then just squeeze to get the water out.
The cooking water is full of oxalic acid, it is used by furniture restorers to get rid of ring marks and water stains.
In years gone by the cooking water was used to put a shine on marble.