The effect is investigated of dietary magnesium (Mg) supplementation on the Mg, calcium (Ca) and phosphorus (P) utilization in Mg-deficient rats. Three-week-old male Wistar rats were fed on either a control diet (control group) or Mg-deficient diet (Mg-deficient group) for 28 days. Half the rats in the Mg-deficient group were then changed from the Mg-deficient diet to the control diet (recovery group) for 14 days. The Mg-deficient group displayed a change in Mg, Ca and P utilization (balance study and serum level). After the diet had been changed, the apparent absorption of Mg, the urinary excretion of Mg and Ca, and the retention of Mg and P were significantly higher in the recovery group than in the Mg-deficient group. The urinary P excretion was also significantly lower in the recovery group than in the Mg-deficient group. The serum Mg and P levels were also significantly higher in the recovery group than in the Mg-deficient group after the diet had been changed, while the serum Ca level was significantly lower in the recovery group than in the Mg-deficient group. The results of this study suggest that the Mg-deficient diet induced changes in the Mg and P balance, and that the serum levels of Mg, Ca and P were restored by changing from the Mg-deficient diet to the control diet.
