Iron metabolism in infants: influence of bovine lactoferrin from iron-fortified formula

Abstract

ObjectiveThe aim of this study was to evaluate whether an iron-fortified formula with a concentration of lactoferrin would significantly improve the hematologic indexes and iron status in term infants compared with those same values in infants fed an iron-fortified formula without lactoferrin. MethodIn this prospective, multicenter, controlled intervention study, 260 infants ages 4 to 6 mo were selected from six maternal and children's health care hospitals in the area. All infants were divided into two groups with the sequence of outpatient: lactoferrin-fortified formula milk group (fortified group, FG, containing lactoferrin 38 mg/100 g milk and iron element 4 mg/100 g milk) and no lactoferrin fortified milk (control group, CG, containing lactoferrin 0 mg/100 g milk and iron element 4 mg/100 g milk) for 3 mo. The levels of weight, height, and head circumference and the concentration of hemoglobin (Hb), serum ferritin (SF), and serum transferring receptor (sTfR) were measured and sTfR-SF index (TFR-F index), total body iron content (TBIC) and low height for age (HAZ), low weight for age (WAZ), and low weight for height (WHZ) were computed before and after the intervention, respectively. ResultsIn all, 213 (115 in FG and 98 in CG) infants completed the intervention trial and all measurements of biochemical indicators. There were no significant differences in the average amount of daily intake of formula milk (94.3 ± 9.8 g versus 88.2 ± 8.7 g for FG and CG; P > 0.05) and iron element (3.8 ± 0.4 mg versus 3.7 ± 0.6 mg for FG and CG; P > 0.05). The average amount of daily intake of lactoferrin for infants in FG group was 35.8 ± 3.7 mg. The levels of weight, WAZ, WHZ, Hb, SF, TFR-F index, and TBIC after intervention of infants in FG were all significantly higher than those of infants in CG weight, 8723 ± 245 g versus 8558 ± 214g; WAZ, 1.02 ± 0.31 versus 0.44 ± 0.18; WHZ, 0.98 ± 0.31 versus 0.41 ± 0.12; Hb, 125.5 ± 15.4 g/L versus 116.9 ± 13.1 g/L; SF, 44.7 ± 17.2 μg/L versus 31.6 ± 18.4 μg/L; TFR-F index, 1.88 ± 0.41 versus 1.26 ± 0.39; TBIC, 6.12 ± 0.78 mg/kg versus 5.26 ± 0.55 mg/kg for FG and CG; P < 0.05), but significantly lower (P < 0.05) for the prevalence of anemia (4.1% versus 7.5%), iron deficiency (13.9% versus 24.4%), and iron-deficient anemia (1.7% versus 6.1%). ConclusionWhen infants who were exclusively breastfed were supplemented with lactoferrin-fortified milk, significant increases in TBIC and iron absorption in the intestine were seen.