Is taking a lot of supplemental calcium in the form of calcium carbonate (oyster shell calcium) bad for stomach health? I've always thought that antacids made from calcium carbonate make the stomach more acidic over time because it tries to compensate for the calcium carbonate. I don't really drink milk because I need more solid food in my diet and I can't get any good milk where I live, so I supplement with calcium to make up for it. Should I be concerned? Thanks for any help!