Risk of hypervitaminosis D from prolonged feeding of high vitamin D premature infant formula.

BACKGROUND

Most premature infant formulas marketed in Japan have high vitamin D content. Potential for vitamin D intoxication was assessed in premature infants with prolonged feeding of such a premature formula vitamin D content, 2700 IU/L.

METHODS

Serum vitamin D, calcium and phosphorus, and urinary calcium, were measured in 12 very premature infants fed premature infant formula, regular formula (vitamin D content; 460 IU/L), and/or mother's milk.

RESULTS

Concentrations of 25(OH)D in sera associated with sole feeding of premature infant formula (n = 40) were significantly higher than sera corresponding to regular formula or breast milk (n = 25; 175 versus 115 nmol/L, P <0.0001). No sample showed a serum 25(OH)D concentration below 25 nmol/L. Of 65 samples, 49 (75.4%) showed 25(OH)D concentrations exceeding 100 nmol/L, but serum calcium and phosphorus concentrations were normal. Unexpectedly, urinary calcium correlated negatively with serum 25(OH)D.

CONCLUSION

In prolonged feeding of premature infant formula with high vitamin D, it was concluded that it could cause a high blood concentration of vitamin D in premature infants, and also that in these infants urine calcium is not a reliable indicator of excessive vitamin D intake.