<<Disclaimer: Verify this information before applying it to your situation.>> There was an interesting show this weekend on a local cable station. An md was talking about the ads by Tums, etc to take antacids for calcium. He ponted out tho, that calcium needs an acid base to be absorbed. Tums, Rolaids etc do just the opposite...theyneutralize acid! The md advised taking a balanced cal/mag supplement. The acids in the stomach will make them work.