title: Iron depletion is associated with daytime bottle-feeding in the second and third years of life.
abstract: OBJECTIVE
  To measure the association between daytime bottle-feeding and iron depletion in young children.
  
  
  METHODS
  Cross-sectional design with concurrent measurement of exposure and outcome. The exposure was the current container (bottle or cup) used for daytime milk consumption. Child, maternal, and dietary variables were collected.
  
  
  METHODS
  Community-based pediatric practice serving a diverse population in an urban Canadian city.
  
  
  METHODS
  One hundred fifty healthy children, aged 12 to 38 months, attending a well-child care visit.
  
  
  METHODS
  Iron depletion (serum ferritin level, <10 microg/L]).
  
  
  RESULTS
  Of the 150 children, 82 (55%) were bottle-fed and 68 (45%) were cup fed. Iron depletion occurred in 29 (37%) of 78 bottle-fed and in 12 (18%) of 67 cup-fed children. The crude relative risk for iron depletion was 1.81 (95% confidence interval, 1.09-3.01). In the final logistic regression model, a significant association between bottle use and iron depletion was identified, beginning after the age of 16 months. At 18 months, the relative risk, adjusted for several child, maternal, and dietary variables, for the association between bottle use and iron depletion was 1.31 (95% confidence interval,1.24-1.47); at 24 months, the adjusted relative risk was 2.50 (95% confidence interval, 2.46-2.53). Milk consumption of more than 16 oz/d occurred in 55 (67%) of the 82 bottle-fed and in 22 (32%) of the 68 cup-fed children (P<.001).
  
  
  CONCLUSIONS
  In the second and third years of life, there is an almost 2-fold association between iron depletion and daytime bottle-feeding compared with cup feeding. The child's age may be a modifier, and milk volume consumed may be a mediator, of this association. Duration of bottle use is a potentially modifiable practice.
authors.affiliation: Department of Pediatrics, University of Toronto Faculty of Medicine, Toronto, Ontario, Canada.
authors.forename: Trenna L
authors.initials: TL
authors.lastname: Sutcliffe
authors.forename: Amina
authors.initials: A
authors.lastname: Khambalia
authors.forename: Shelley
authors.initials: S
authors.lastname: Westergard
authors.forename: Sheila
authors.initials: S
authors.lastname: Jacobson
authors.forename: Michael
authors.initials: M
authors.lastname: Peer
authors.forename: Patricia C
authors.initials: PC
authors.lastname: Parkin
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000453:epidemiology*; D000818:Animals; D001903:Bottle Feeding / Q000009:adverse effects*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004327:Drinking Behavior; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D007223:Infant; D000090463:Iron Deficiencies; D016015:Logistic Models; D008297:Male; D008892:Milk
chemical_list: D005293:Ferritins