FORTIFICATION OF HUMAN-MILK - EVALUATION OF A NOVEL FORTIFICATION SCHEME AND OF A NEW FORTIFIER

Human milk fed to very-low-birth-weight infants must be fortified with protein, minerals, and vitamins. We tested a new fortification regime n in which the amount of fortifier was adjusted on the basis of freque nt determinations of serum urea nitrogen (SUN). A newly formulated for tifier based on bovine milk proteins was employed either in the new fa shion (regimen ADJ) or in the conventional fixed proportion (regimen F IX). Using the fixed proportion, the study also compared the new forti fier with a fortifier based on human milk protein (regimen HMP). Twelv e infants were studied with each of the three regimens; nearly all com pleted 3 weeks of study. Protein intake was generally higher in ADJ th an FIX; the difference was significant (p < 0.01) during week 2. Weigh t gain was somewhat (but not significantly) greater in regimen ADJ (32 .3 g/d or 18.8 g/kg/d) than in regimen FIX (30.0 g/d or 18.3 g/kg/d). SUN was higher in ADJ than in FIX, and several other serum chemical va lues (calcium, phosphorus, potassium) tended to be higher, probably re flecting higher intakes of these nutrients with ADJ than with FIX. Pla sma concentrations of several amino acids were higher in ADJ than FIX, but none, including threonine, were outside the physiological range. In comparing regimen FIX to regimen HMP, infants on FIX received simil ar intakes of protein and showed slightly but not significantly more r apid weight gain. Concentrations of SUN were lower with FIX, but other serum chemical values, including amino acids, were generally similar to HMP. We conclude that use of the new adjustable fortification regim en is feasible and safe and that it should be studied further. It prod uced the expected increases in nutrient intakes and growth. The new bo vine milk-based fortifier appears to be equivalent to the human milk-b ased fortifier.