Both salt-loading studies and reports of free-living populations find
that urinary calcium excretion increases approximately 1 mmol (40 mg)
for each 100 mmol (2300 mg) increase in dietary sodium in normal adult
s. Renal calcium stone-formers with hypercalciuria appear to have grea
ter proportional increases in urinary calcium (approximately 2 mmol) p
er 100 mmol increase in salt intake. Thus, reduction of dietary NaCl m
ay be a useful strategy to decrease the risk of forming calcium-contai
ning kidney stones.