Just watched a video on the work of Norman Walker, one of the leading figures in the use of fresh raw juices for healing, who lived to a ripe old age around a 100 years after being diagnosed with advanced liver cirrhosis when he was 55. He draws a huge distinction between cooked and raw oxalic acid, basically giving a big healthy thumbs up to the raw form and a thumbs down to the cooked form which he says can cause trouble in the body.