Magnesium Balance Studies with Infants

Infants from 2 to 6 months of age may be maintained in small but definite positive magnesium balance on diets containing 10 to 20 mg. per kilogram of body weight per day. Retentions are of greater magnitude when the intake is more than 20 mg. per kilogram per day. No definite relationship was noted: (1) between magnesium and calcium retentions although there was a slight tendency for the retention of both substances to vary in the same direction; (2) between the fecal phosphorus excretion and the magnesium content of the feces or the magnesium retention; and (3) between the level of vitamin D and the magnitude of magnesium retention. Although the data are not conclusive, slightly better retentions were found when honey was the source of carbohydrate than were observed when corn syrup was added. The variations noted for the different types of milk used can probably be ascribed to the level of magnesium intake.