Calcium, magnesium and phosphorus in the nutrition of the newborn.

Several factors have been suggested to contribute to inadequate bone mineralization in infants. Calcium and phosphorus intakes in preterm infants are below the intrauterine accretion rates. Calcium retention is influenced by the types of calcium salts used and by alterations in dietary phosphorus, fat and carbohydrates. Dietary intakes of vitamin D, and modifications in the protein base of infant formula, e.g., soy base vs cow milk base, may impact bone mineralization. The major hormonal mechanisms involved in the regulation of bone mineralization are parathyroid hormone, calcitonin and vitamin D. From recent animal studies, it has been suggested that parathyroid hormone related peptide (PTH-rp) may also play a role in perinatal calcium homeostasis.