calcium question

Hi All, I was talking w/some friends the other day and this question came up about calcium. Why is it that you can absorb calcium from a pill but not from food....I had no good answer. Can anyone out there answer this for me? Thanks, Melissa

I am no expert but it is my understanding that we do absorb SOME from food. The problem with certain nutrients--especially calcium and iron, is that they are primarily absorbed in the duodenum, which is the part of our intestine which is bypassed. I think I read that when calcium levels are high then it is also absorbed in the colon. http://www.vivo.colostate.edu/hbooks/pathphys/digestion/smallgut/absorb_minerals.html