In defence of calcium

Nordin, B E Christopher

doi:10.5694/j.1326-5377.2011.tb04133.x

Topics

Health services administration

Cardiovascular diseases

Endocrine system diseases

Reports of adverse events related to calcium supplementation should be supported by rigorous evidence

Calcium is an essential nutrient, not only because of its major role in bone, where 99% of it is stored, but because of its central role in neuromuscular function. It is this latter role that explains why ionised calcium in the blood and tissue fluids is one of the most tightly controlled analytes of those that are commonly measured.1 However, maintenance of the calcium level in tissue fluids carries with it the penalty of continuous loss of calcium through the kidneys, bowel and skin, even on a low calcium intake, which is why the recommended daily calcium allowance for adults is relatively high, at 1000 mg.2

1 Endocrine and Metabolic Unit, Royal Adelaide Hospital, Adelaide, SA.
2 Discipline of Medicine, University of Adelaide, Adelaide, SA.

Correspondence: christopher.nordin@imvs.sa.gov.au

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