Early cow's milk introduction is associated with failed personal-social milestones after 1 year of age

William E. Bennett, Kristin S. Hendrix, Rachel T. Thompson-Fleming, Stephen M. Downs, Aaron E. Carroll

Research output: Contribution to journalArticle

1 Scopus citations


Both the American Academy of Pediatrics (AAP) and the Institute of Medicine (IOM) recommend delaying the introduction of cow's milk until after 1 year of age due to its low absorbable iron content. We used a novel computerized decision support system to gather data from multiple general pediatrics offices. We asked families whether their child received cow's milk before 1 year of age, had a low-iron diet, or used low-iron formula. Then, at subsequent visits, we performed a modified developmental assessment using the Denver II. We assessed the effect of early cow's milk or a low-iron diet on the later failure of achieving developmental milestones. We controlled for covariates using logistic regression. Early cow's milk introduction (odds ratio (OR) 1.30, p=0.012), as well as a low-iron diet or low-iron formula (OR 1.42, p<0.001), was associated with increased rates of milestone failure. Only personal-social milestones (OR 1.44, p=0.002) showed a significantly higher rate of milestone failure. Both personal-social (OR 1.42, p<0.001) and language (OR 1.22, p=0.009) showed higher rates of failure in children with a low-iron diet. Conclusions: There is an association between the introduction of cow's milk before 1 year of age and the rate of delayed developmental milestones after 1 year of age. This adds strength to the recommendations from the AAP and IOM to delay cow's milk introduction until after 1 year of age.

Original languageEnglish (US)
Pages (from-to)887-892
Number of pages6
JournalEuropean Journal of Pediatrics
Issue number7
StatePublished - Jul 2014



  • Cow's milk
  • Development
  • Developmental delay
  • Iron deficiency

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Medicine(all)

Cite this