Calcidophilus provides a source of bio-available, milk-free calcium. During the growing process of the Lactobacillus acidophilus, calcium carbonate is fed to the friendly bacteria which incorporates the calcium into its own structure. When the L. acidophilus has digested sufficient calcium it is freeze-dried and encapsulated, then vacuum packed into glass bottles. Generally, ordinary calcium carbonate is poorly absorbed. When ingested the calcium-rich L. acidophilus attach to the intestinal wall and release calcium.