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Iron Status at Age 6 Months in Colombian Infants Exclusively Breast-fed for 4 to 5 Versus 6 Months
Gilma A Olaya1, Margaret Lawson, Mary Fewtrell
1*Nutrition and Biochemistry Department, Faculty of Sciences, Pontificia Universidad Javariana, Bogota, Colombia †Childhood Nutrition Research Centre, UCL Institute of Child Health, London, United Kingdom.
Insights
Exclusive breast-feeding (EBF) for 4-5 months versus 6 months in infants did not significantly impact anaemia or iron deficiency at 6 months. However, both conditions were common, highlighting the need for continued monitoring and avoidance of cow's milk before 12 months.
Area of Science:
- Pediatric Nutrition
- Infant Health
- Hematology
Background:
- Prolonged exclusive breast-feeding (EBF) protects infants from infections but may increase the risk of iron deficiency (ID) and anaemia (IDA).
- The optimal timing for introducing complementary foods alongside breast milk can vary by geographical and socioeconomic factors.
- Iron deficiency anaemia is a significant global health concern in infants, impacting development and well-being.
Purpose of the Study:
- To compare the prevalence of anaemia, iron deficiency, and iron deficiency anaemia in 6-month-old infants exclusively breast-fed for 4-5 months versus those exclusively breast-fed for 6 months or longer.
- To identify predictors of anaemia and iron deficiency in this infant population.
- To assess the safety and implications of different durations of exclusive breast-feeding on infant iron status.
Main Methods:
- An observational study was conducted on healthy, term infants in Bogota, Colombia, all exclusively breast-fed for at least 4 months.
- Infant feeding practices, anthropometric measurements, and blood samples for haemoglobin (Hb) and serum ferritin (SF) analysis were collected at 6 months of age.
- Statistical analyses, including multivariate models, were used to compare outcomes between feeding groups and identify predictive factors.
Main Results:
- The prevalence of anaemia (20%), ID (10%), and IDA (5%) was high at 6 months but did not differ significantly between infants exclusively breast-fed for 4-5 months and those exclusively breast-fed for 6 months.
- Greater weight gain from 0-6 months and caesarean delivery predicted anaemia, while greater weight gain also predicted ID.
- Lower haemoglobin levels were observed in infants with higher cow's milk intake, and lower serum ferritin in boys and those with greater weight gain.
Conclusions:
- Exclusive breast-feeding for 6 months appears safe in this population regarding anaemia and iron deficiency at 6 months.
- Anaemia and iron deficiency are common at 6 months, underscoring the need for continued research into later iron status.
- The study emphasizes the importance of avoiding cow's milk introduction before 12 months of age to prevent potential negative impacts on infant iron status.
Objectives:
The optimal age for introducing complementary feeding to breast-fed infants may differ depending on the setting. Prolonged exclusive breast-feeding (EBF) protects against infection but may increase the risk of iron deficiency (ID)/anaemia (IDA) in vulnerable infants. The aim of the present study was to compare haemoglobin (Hb), serum ferritin (SF), anaemia (Hb < 11 g/L), ID (SF < 12 μg/L) and IDA (Hb < 10.5 g/dL + Hct < 33% + ID) using observational analyses in 6-month old infants from Bogota, Colombia who were EBF for 4 to 5 versus 6 months or older, and examine predictors.
Methods:
Infant feeding was recorded, anthropometry performed, and blood obtained for Hb and SF at 6 months in healthy term infants (birth weight > 2500 g), all EBF for ≥4 months.
Results:
One hundred eight infants (54% boys) were recruited; 46% EBF for 4 to 5 months, 54% EBF at 6 months. Prevalence of anaemia, ID, and IDA was 20%, 10%, and 5%, with no significant difference between EBF4-5 and EBF6 groups. In multivariate models, anaemia/ID were predicted by greater weight gain from 0 to 6 months, and anaemia also by caesarean delivery; Hb was lower in infants with higher intake of cows' milk; SF was lower in boys and those with greater weight gain. EBF4-5 versus EBF6 was not a significant predictor of any outcome.
Conclusions:
Anaemia and ID were common at 6 months but were not affected by EBF for 4 to 5 versus 6 months, suggesting 6 months EBF is safe in this population. Further research is, however, required to examine effects on later iron status. The findings highlight the need to emphasise avoidance of cow's milk before 12 months.
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