title: Breastfeeding and IQ Growth from Toddlerhood through Adolescence.
abstract: OBJECTIVE
  The benefits of breastfeeding for cognitive development continue to be hotly debated but are yet to be supported by conclusive empirical evidence.
  
  
  METHODS
  We used here a latent growth curve modeling approach to test the association of breastfeeding with IQ growth trajectories, which allows differentiating the variance in the IQ starting point in early life from variance in IQ gains that occur later in childhood through adolescence. Breastfeeding (yes/ no) was modeled as a direct predictor of three IQ latent growth factors (i.e. intercept, slope and quadratic term) and adjusted for the covariates socioeconomic status, mother's age at birth and gestational stage. Data came from the Twins Early Development Study (TEDS), a prospective cohort study of twins born between 1996 and 1994 in the United Kingdom, who were assessed 9 times on IQ between age 2 and 16 years (N = 11,582).
  
  
  RESULTS
  Having been breastfed was associated with a small yet significant advantage in IQ at age 2 in girls (β = .07, CI 95% from 0.64 to 3.01; N = 3,035) but not in boys (β = .04, CI 95% from -0.14 to 2.41). Having been breastfeeding was neither associated with the other IQ growth factors in girls (slope: β = .02, CI 95% from -0.25 to 0.43; quadratic: β = .01, CI 95% from -0.02 to 0.02) nor in boys (slope: β = .02, CI 95% from -0.30 to 0.47; quadratic: β = -.01, CI 95% from -0.01 to 0.01).
  
  
  CONCLUSIONS
  Breastfeeding has little benefit for early life intelligence and cognitive growth from toddlerhood through adolescence.
authors.affiliation: Department of Psychology, Goldsmiths University of London, London, United Kingdom.
authors.forename: Sophie
authors.initials: S
authors.lastname: von Stumm
authors.affiliation: King's College London, MRC Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom.
authors.forename: Robert
authors.initials: R
authors.lastname: Plomin
mesh_terms: D000293:Adolescent; D041923:Adolescent Development; D001942:Breast Feeding; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D005260:Female; D057238:Growth Charts; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D011446:Prospective Studies; D014427:Twins; D006113:United Kingdom