@nycmusic I did some reading on this when I learned that the old advice to eat spinach for calcium is now known to be wrong.

The below video (by 2 Canadian doctors) briefly describes spinach as fairly bad for calcium. But other sources (sorry, I did not save the references) said that spinach was believed to be only neutral for calcium. They suggested that spinach contains only enough oxalates to neutralize its own calcium, but not other calcium that you might take. The video below still says to eat lots leafy greens like spinach, but pair with calcium from elsewhere, as you mention in your post.