Like other supplements, neither the FDA nor any other federal or state agency routinely tests calcium products for quality prior to sale. While calcium is not a very expensive raw material, it can be bulky, making the formulation of calcium supplements more complex. Many sources of calcium naturally contain other minerals such as lead. In children, infants, and fetuses, even low levels of lead can adversely affect neurobehavioral development and cognitive function. In adults, lead at somewhat higher levels can cause elevated blood pressure, anemia, and adversely affect the nervous and reproductive systems.
Lead is of particular concern during pregnancy as the mother can deliver it to the fetus.
The USP, however, does not verify that products bearing the USP designation meet these standards, which includes the amount of calcium in the product. None of the products failed testing for exceeding contamination levels for lead or the other metals evaluated. Manufacturers may change product ingredients and information at any time, so be sure to check labels carefully when evaluating the products you use or buy. If a product's ingredients differ from what is listed above, it may not necessarily be of the same quality as what was tested. All rights reserved.