Infant formula iron fortification of 2 vs. 8 mg/L does not increase the risk of iron deficiency or impact neurodevelopment at 12 months.

OBJECTIVES

The aim of this follow-up was to investigate how reduced iron concentration and added bovine lactoferrin in infant formula affect neurodevelopment, iron status, and growth at 12 months of age.

METHODS

Swedish healthy term formula-fed infants (n = 180) were randomly assigned to receive, from 6 weeks to 6 months of age, a low-iron formula (2 mg/L) fortified with bovine lactoferrin (1.0 g/L) (Lf+, n = 72), the same formula without lactoferrin fortification (Lf-, n = 72) or a control standard formula with 8 mg/L and no lactoferrin (CF, n = 36). Breast-fed infants were recruited as a reference (n = 72). At 12 months of age, Bayley Scales of Infant and Toddler Development-III (BSID-III), iron status, and anthropometrics were assessed.

RESULTS

There were no intervention effects on BSID-III. Explored outcomes were unaffected by lactoferrin and the two low-iron groups (Lf+ and Lf-) were combined. The low-iron group had lower hepcidin (37.8 vs. 49.4 ng/mL, p = 0.027), compared to the CF group. Furthermore, they had iron status indicators more similar to the breast-fed reference group. The prevalence of iron deficiency (ID) and iron deficiency anemia (IDA) was low with no significant differences among groups. Weight and length were unaffected by intervention, however head circumference was minimally higher in infants fed low-iron formula compared to CF with mean difference (95% confidence interval) of 0.3 (0.0-0.6) standard-deviation-scores, p = 0.03.

CONCLUSIONS

Infant formula iron concentration at 2 mg/L was adequate in this population of infants with low risk of ID. Adding bovine lactoferrin did not affect the explored long-term clinical outcomes.