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Evaluation of two iron-fortified, milk-based formulas during infancy
C K Bradley1, L Hillman, A R Sherman
1Mead Johnson Research Center, Evansville, IN 47721-0001.
Insights
Iron-fortified infant formulas support healthy growth and iron levels in babies. Both 7.4 and 12.7 mg/L iron formulas are well-tolerated and effective alternatives to breast milk for infant nutrition.
Area of Science:
- Pediatric Nutrition
- Infant Health
- Iron Metabolism
Background:
- Optimal infant nutrition is crucial for growth and development.
- Iron is an essential nutrient for infants, and deficiency can lead to developmental issues.
- Breast milk is the recommended source of nutrition, but infant formulas are common alternatives.
Purpose of the Study:
- To compare the efficacy and tolerance of two iron-fortified milk-based infant formulas (7.4 mg/L and 12.7 mg/L iron) against breast-feeding.
- To assess infant growth, iron status, and formula tolerance during the first year of life.
Main Methods:
- A partially randomized, double-blind trial involving 347 healthy, term infants.
- Infants were assigned to receive one of two iron-fortified formulas or were breast-fed.
- Growth, iron status (hemoglobin, hematocrit, ferritin), and tolerance indicators were measured at 6 and 12 months.
Main Results:
- No significant differences in growth or iron status were observed between the two formula groups.
- Breast-fed infants showed significantly less weight and length gain in the first 6 months compared to formula-fed infants.
- The high-iron formula group had significantly higher serum ferritin levels than both low-iron formula and breast-fed groups, though all remained within normal ranges.
Conclusions:
- Milk-based formulas with 7.4 mg/L or 12.7 mg/L iron adequately support normal growth and iron status in healthy term infants.
- Both iron concentrations in the tested formulas are well-tolerated and accepted by infants.
- Iron-fortified formulas provide a viable nutritional option for infants during their first year.
Objective:
Compare milk-based, iron-fortified formulas containing 7.4 and 12.7 mg/L iron and breast-feeding during the first year of life.
Design:
Partially randomized, double-blind trial: non-breast-fed infants randomly assigned to receive one of two coded formulas, identical except for iron content; infants discontinuing breast-feeding between 1 and 8 weeks of age randomly assigned to a formula late-start group.
Setting:
Five general community pediatric practices in Missouri, Indiana, Illinois, and Pennsylvania.
Participants:
Sample of 347 healthy, term infants, enrolled within 1 week after birth; 172 included in statistical analyses.
Outcome Measures:
Length, weight, and indicators of formula intolerance recorded at clinic visits; formula consumption, bowel movements, stool consistency, and other tolerance indicators recorded by parents on daily and weekly report forms; hemoglobin, hematocrit, and serum ferritin, iron zinc, and copper measured at 6 and 12 months.
Results:
No significant differences between formula-fed groups in growth, attrition, formula consumption, bowel movements, hematocrit, hemoglobin level, and serum iron, zinc, and copper levels (P > .05); first 6-month weight and length changes of the breast-fed group significantly less than in both formula-fed groups (P < .008); serum ferritin level of the formula-fed, high-iron group significantly higher than that of the low-iron and breast-fed groups (P < .008), although all groups' values were normal; no apparent differences between formula groups in formula tolerance and stool characteristics but data were not analyzed statistically.
Conclusions:
Milk-based formulas containing either 7.4 or 12.7 mg/L iron support normal growth and iron status of healthy, term, normally fed infants during the first year and both are well tolerated and accepted.
