Aging humans lose calcium from their bones so that in time they become fragile, a condition known as osteoporosis . Osteoporosis is estimated to cause some 1.5 million fractures each year in the U. S. One in every three women who survive to age 81 will have suffered a hip fracture because of osteoporosis. Much of the calcium in supplements fails to be absorbed and passes out in the feces. The calcium in the most popular supplements is in the form of calcium carbonate. The calcium in some other brands comes from powdered oyster shells.
Calcium carbonate is insoluble in water.
There really is little to indicate that these supplements halt, let alone reverse, osteoporosis. For women after menopause, treatment with estrogens seems to be the most effective way to avoid osteoporosis. Time should tell. Exercise as well.