title: The 30-second effect: an experiment revealing the impact of television commercials on food preferences of preschoolers.
abstract: OBJECTIVE
  To examine whether televised food commercials influence preschool children's food preferences.
  
  
  METHODS
  In this randomized, controlled trial, preschool children viewed a videotape of a popular children's cartoon either with or without embedded commercials. Children were then asked to identify their preferences from pairs of similar products, one of which was advertised in the videotape with embedded commercials. Preschoolers' parents were interviewed to determine children's demographic characteristics and media use patterns.
  
  
  METHODS
  Forty-six 2- to 6-year-olds from a Head Start program in northern California.
  
  
  METHODS
  For demographic and media use characteristics, univariate data were examined and Student t and chi 2 tests were used to test for differences between the control and treatment groups. We calculated the Cochran Q statistic to assess whether the proportion of those choosing advertised food items was significantly higher in the treatment group than in the control group.
  
  
  RESULTS
  Children exposed to the videotape with embedded commercials were significantly more likely to choose the advertised items than children who saw the same videotape without commercials (Qdiff = 8.13, df = 1, P < .01).
  
  
  CONCLUSIONS
  Even brief exposures to televised food commercials can influence preschool children's food preferences. Nutritionists and health educators should advise parents to limit their preschooler's exposure to television advertisements. Furthermore, advocates should raise the public policy issue of advertising and young children, especially given the recent epidemic of childhood obesity and the ever-changing media environment.
authors.affiliation: Stanford Center for Research in Disease Prevention, Palo Alto, Calif., USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Borzekowski
authors.forename: T N
authors.initials: TN
authors.lastname: Robinson
mesh_terms: D000329:Advertising; D002140:California; D002648:Child; D002675:Child, Preschool; D005260:Female; D005518:Food Preferences / Q000523:psychology*; D006801:Humans; D008297:Male; D013690:Television; D014743:Videotape Recording