If we need about 1500 mg of calcuim/day.(BTW where did this # come
from?-seems they keep raising it every few years) And plants are a poor
source of calcium (we would have to eat a lot of spinach and broccoli to get
this much). Where did our paleo ancestors get enough without supplements?

Currently I supplement with 500 mg of calcium citrate and 250 mg magnesium
citrate because I fear I am not getting enough calcium and magnesium in my
diet although I eat some form of leafy green vegetables daily and sardines
3-4 times per week.

Can anyone estimate how much sardines/ leafy greens we need to consume to
reach 1500 mg of calcium (and magnesium, for that matter)