Iron balances in infant nutrition

Area of Science:

• Pediatric Nutrition
• Infant Metabolism
• Mineral Balance Studies

Background:

• Establishing optimal infant nutrition is crucial for healthy development.
• Understanding iron absorption and retention in early infancy is vital for preventing deficiencies.
• Different feeding methods, including breastfeeding and formula feeding, impact nutrient bioavailability.

Purpose of the Study:

• To compare iron balance in term male infants fed breast milk, standard infant formula, or iron-fortified infant formula.
• To quantify iron intake and retention across different feeding regimens from 3 to 17 weeks of life.
• To evaluate the efficacy of iron-fortified formula in promoting iron retention during early infancy.

Main Methods:

• Conducted home-based iron balance studies in 17 full-term male infants over 5 periods between the 3rd and 17th week of life.
• Utilized three 24-hour collections per period to measure iron intake and excretion.
• Compared three feeding groups: breast-fed (n=10), standard formula (P1, 1.1 mg iron/L, n=3), and iron-fortified formula (P2, 10.35 mg iron/L, n=4).

Main Results:

• Breast-fed infants retained 0.09 mg iron/kg body weight/day.
• Infants on standard formula (P1) showed negative iron retention (-0.01 to -0.5 mg/kg/day).
• Infants on iron-fortified formula (P2) exhibited significantly higher iron retention (1.13 to 3.66 mg/kg/day), 12 to 40 times more than breast-fed infants.

Conclusions:

• Standard infant formula (P1) is associated with poor iron retention in early infancy.
• Iron-fortified infant formula (P2) significantly enhances iron retention compared to both breast milk and standard formula.
• Dietary iron content plays a critical role in determining iron balance during the first months of life.