It is interesting that you mentioned that it was Gods intention for adults to get their calcium from green leafy vegtables. Right now, my child only eats brown, white and yellow items - green things can not even sit on her plate. I do have to be concerned about her getting enough calcium. It would be nice if my child, or even if I liked mustard greens because of the huge calcuim content it would supply to our bodies, however that ain't happenin'. Calcium supplements are a necessity for most females.