Abstract
Succeeding to the former reports, with the similar purpose to obtain the data for the calcium requirement of Japanese children under ten years old: five school boys and one kindergarden boy were taken as subjects of this experiment.
Fifteen days experimental period: from 28, July to 11, Augast 1956, was divided into 3 stages of equal length. The first was the stage for the standard experimental diet, containing calcium as much as 10mg. per kg, of body weight. In the second and the third stadium the subjects were divided into two groups and one group was given 180ml. of milk as a source of calcium in the second stadium and 0.5mg of calcium carbonate in the third to be able to take equal amount of calcium as in the second stadium. The other group was given in reverse order.
By the result, in the first stadium, all subjects showed positive calcium balance: 51mg of retention for the average intake of 221mg. In the second and third stadium, according to the increase of calcium intake about 210mg, as the amount of retention 161mg and 145mg were obtained respectively.
In this experiment, none of the subjects showed a negative calcium balance and the intake of 5.0mg per kg. of body weight was seemed to be necessary for the maintenance of its balance.
Throughout the total period, the subjects showed calcium retention of 118mg on an average to the intake of 362mg per day. It means that 5.3mg of calcium was retained to the intake of 16.3mg per kg. of body weight.
