This doesn't make sense to me. 200g of cooked rhubarb already has almost 400mg of calcium which is almost half of the 1000mg daily US recommendation and more than half of the 700mg daily UK recommendation.
Thinking dairy is the only source of calcium is meme-nutrition like eating bananas for potassium especially when talking about a food already high in calcium.
Do you know why doesn't the Oxalic acid bind with the calcium of the Rhubarb, and turns into a problem if consumed? Is there enough calcium to bind with the Oxalic acid? Is the calcium in Rhubarb bioavailable?
Genuine questions here, because as I understand, many of the nutricional fact sheets are calculated after the food is broken down and passed though a mass spectrometer.
I'm living in Finland, and that is where I got that knowledge from. So yes, unfortunately my source is also empirical knowledge.
But knowing how certain African cultures learned to neutralize Cassava, and that knowledge passed through generations without knowing the reason why, I learned to not fully dismiss these kinds of knowledge...
Interesting. I'm in New Zealand and hadn't come across this. Being a commonwealth country makes me suspect it's not common knowledge in England either. Or has perhaps as you mention the reasons have been lost over time.
Thinking dairy is the only source of calcium is meme-nutrition like eating bananas for potassium especially when talking about a food already high in calcium.