Human milk lacto-engineering. Growth nitrogen metabolism, and energy balance in preterm infants.

Fourteen 3-day metabolic balance studies were carried out in 8 healthy male preterm infants (birthweight 1 270 +/- 170 g, gestational age 30 +/- 2 weeks) fed 183 +/- 7 ml/kg/day of a human milk formula made of incompletely skimmed human milk enriched with lyophilized whole human milk, minerals, medium chain triglycerides and linoleate. Daily intakes per kilo bodyweight were for protein 3.5 +/- 0.3 g, fat 7.0 +/- 2.1 g, and energy 573 +/- 88 kJ (137 kcal). Weight gain was 29 +/- 5 g per day and nitrogen retention was 317 +/- 52 mg/kg/day. Fat absorption was 76 +/- 12%. Renal acid and solute loads were low and there was no metabolic acidosis, hyperazotemia or hyperaminoacidemia, except for tyrosine. It is concluded that preterm infants fed a human milk formula have similar growth rates and nitrogen retentions as foetuses in utero or preterm infants fed their own mother's milk.