The purpose of this study was to determine the efficacy of early low-dose iron supplementation in term breast-fed infants.

Eighty-seven healthy term infants were divided into 3 groups: A, formula-fed; B, breast-fed only; S, breast-fed with iron supplementation (5 mg/day from 2 months of age). We measured ferritin, iron, total iron binding capacity (TIBC), transferrin saturation rate (TFSAT), hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and red cell distribution width (RDW) at birth, 6 months of age, and 12 months of age.

1) At 6 months of age, ferritin, iron, TFSAT, and Hb in Group B were the lowest among the 3 groups, whereas TIBC and RDW were the highest. The incidences of iron deficiency (ID) and iron deficiency anemia (IDA) in Group B were 33% and 30%, respectively, significantly higher than those seen in Groups A (5% and 8%, respectively) and S (7% and 5%, respectively). 2) At 12 months of age, ferritin, TFSAT, Hb, MCV, and MCH in Group B were the lowest among the 3 groups, whereas TIBC and RDW were the highest. Iron and Hct did not differ among the 3 groups. The incidences of ID and IDA in Group B were 64% and 50%, respectively, again significantly higher than those seen in Groups A (4% and 3%, respectively) and S (9% and 7%, respectively).

The prevalences of ID and IDA were higher in breast-fed infants than in formula-fed infants, even at 6 months of age. Early and low-dose iron supplementation in breast-fed infants improved iron status and lowered the incidence of iron deficiency anemia in early infancy.