Calcium Metabolism of Preschool Children

Calcium metabolism has been studied in eight preschool children, four on average calcium intake of 1122 mg., and four on an intake of 775 mg. The basal diet was supplemented with ascorbic acid, potassium citrate, and orange juice as indicated. The results were as follows:1Calcium retentions during 16 weeks averaged 131 ± 50 mg. on the higher level of intake, and 96 ± 26 mg. on the lower level.2The addition of 100 mg. of ascorbic acid to a diet containing 23 to 25 mg. of the vitamin did not significantly increase the retention of calcium.3The addition of 3.38 gm. of potassium citrate lowered the urinary excretion of calcium in all eight subjects but did not significantly alter the calcium retention.4On the substitution of orange juice for crystalline ascorbic acid and potassium citrate supplements, the retentions of calcium were not significantly altered.5In at least five of the eight subjects the absorption of calcium did not appear to be the main factor regulating its retention.6In these eight children factors other than diet alone regulated calcium retention during the 16 weeks of observation.