It really sent me into a spin recently when I read over at Healthy Home Economist that it’s best not to eat spinach and silverbeet raw. Whaaat? Why?
Apparently because they contain oxalic acid, which “blocks iron and calcium absorption and may contribute to the formation of kidney stones.”
*UPDATED: I was so gutted about this, but then my friend Jessica did some digging and discovered several published studies that have proven it’s not so bad eating raw spinach after all. This is especially true if you consume probiotics regularly – in natural yoghurt and kefir.
I’m still not eating as much raw spinach and silverbeet as I used to – we’re not including it in our smoothies anymore, but I’m fine to put spinach leaves in salads and on hamburgers.
If you are at all concerned about this, or have a history of kidney stones, oxalic acid can be reduced by a light steam or boil. Tip out the cooking water though, as that’s where the oxalic acid ends up.
I had a bit of spare time recently, so I cooked up a big batch of spinach and then a big batch of silverbeet and froze them in ziplock bags to use in lasagne and frittatas in the future. I don’t like the taste of cooked spinach much, so I have to disguise it in meals with lots of other ingredients.
1. Bring a big pot of water to the boil.