Avoid Vegetables with Oxalic Acid?

I've heard that spinach, as well as some other vegetables contain significant amounts of oxalic acid, which can interfere with absorption of some minerals. What you think about the oxalic acid issue?
Oxalic acid is a natural product found in spinach and some other plant foods including rhubarb. (Levels are so high in rhubarb leaves that we don't eat them - they're poisonous). It imparts a sharp taste to beet greens and chard that I don't like, especially in older leaves. Concentrations of oxalic acid are pretty low in most plants and plant-based foods, but there's enough in spinach, chard and beet greens to interfere with the absorption of the calcium these plants also contain. For example, Read more...

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