title: Height and adiposity among children.
abstract: OBJECTIVE
  Although BMI (kilograms per meter squared) is widely used as a surrogate measure of adiposity, it is moderately associated (r approximately 0.3) with height among children. We examined whether the resulting preferential classification of taller children as overweight, based on a BMI > or = 95th percentile, is appropriate.
  
  
  METHODS
  We assessed the cross-sectional relation of height among 5- to 18-year-old subjects (n = 1180) to levels of BMI, the sum of 10 skinfold thicknesses, and percentage body fat as determined by DXA.
  
  
  RESULTS
  The prevalence of a BMI level > or = 95th percentile was substantially higher among 5- to 11-year-old subjects who were relatively tall for their age than among shorter children. Among 5- to 8-year-old boys, for example, each SD increase in height-for-age was associated with a 4.6-fold increase in the prevalence of overweight (p < 0.001). Height not only was associated with BMI but also showed similar correlations with the skinfold sum and with percentage body fat; furthermore, the magnitudes of these associations decreased with age. We also found that the association between percentage body fat and BMI (r = 0.85 to 0.90) was close to the maximum correlation that can be achieved by any weight-height index.
  
  
  CONCLUSIONS
  The use of BMI, which preferentially classifies taller young children as overweight, is appropriate because height and adiposity are correlated before the age of 12 years.
authors.affiliation: Division of Nutrition and Physical Activity, Centers for Disease Control and Prevention, Mailstop K-26, 4770 Buford Highway, Atlanta, GA 30341-3717, USA. DFreedman@CDC.gov
authors.forename: David S
authors.initials: DS
authors.lastname: Freedman
authors.forename: John C
authors.initials: JC
authors.lastname: Thornton
authors.forename: Zuguo
authors.initials: Z
authors.lastname: Mei
authors.forename: Jack
authors.initials: J
authors.lastname: Wang
authors.forename: William H
authors.initials: WH
authors.lastname: Dietz
authors.forename: Richard N
authors.initials: RN
authors.lastname: Pierson
authors.forename: Mary
authors.initials: M
authors.lastname: Horlick
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000293:Adolescent; D001823:Body Composition; D001827:Body Height; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D012885:Skinfold Thickness; D011795:Surveys and Questionnaires