Originally Posted by CdCf

That was my first reaction as well, until I did the math.
Turns out watercress has a (my own just-invented term follows...) "specific calcium" of 1200 mg/kg.
Which happens to be about the same as for normal milk (1100-1300 mg/kg).

Let's say a normal person drinks 0.3 l of milk a day. That only "needs" to be replaced by 300 g of watercress, or a a similar amount of a combination of several calcium-rich foods.

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