Abstract
The influence of vitamin B_<12> administration on the values of vitamin B_<12> in blood of boys and girls, 12-13 years of age, was investigated. One tablet of vitamin B_<12> per day was given to 38 children in an orphanage of Osaka for a year and plasebos were given to other 50 children living at the same asylum. The difference between the above two groups of vitamin B_<12> values in whole blood before each administration was not statistically significant. After the administration of 25 μg of vitamin B_<12> per day for two months and a half, the mean value of vitamin B_<12> in whole blood of the children was increased, although some of them did not show any change. The mean value of vitamin B_<12> in whole blood after the administration of vitamin B_<12> for 2.5 months was higher than that of control group, and thereafter the values of the two groups were in parallel. After 3 months discontinuation of the administration, the mean values of vitamin B_<12> concentration in whole blood did not differ significantly between the two groups.
