title: Adiposity and TV viewing are related to less bone accrual in young children.
abstract: OBJECTIVE
  To examine the relation between baseline fat mass and gain in bone area and bone mass in preschoolers studied prospectively for 4 years, with a focus on the role of physical activity and TV viewing.
  
  
  METHODS
  Children were part of a longitudinal study in which measures of fat, lean and bone mass, height, weight, activity, and diet were taken every 4 months from ages 3 to 7 years. Activity was measured by accelerometer and TV viewing by parent checklist. We included 214 children with total body dual energy x-ray absorptiometry (Hologic 4500A) scans at ages 3.5 and 7 years.
  
  
  RESULTS
  Higher baseline fat mass was associated with smaller increases in bone area and bone mass over the next 3.5 years (P < .001). More TV viewing was related to smaller gains in bone area and bone mass accounting for race, sex, and height. Activity by accelerometer was not associated with bone gains.
  
  
  CONCLUSIONS
  Adiposity and TV viewing are related to less bone accrual in preschoolers.
authors.affiliation: Division of General and Community Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA. karen.wosje@cchmc.org
authors.forename: Karen S
authors.initials: KS
authors.lastname: Wosje
authors.forename: Philip R
authors.initials: PR
authors.lastname: Khoury
authors.forename: Randal P
authors.initials: RP
authors.lastname: Claytor
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Copeland
authors.forename: Heidi J
authors.initials: HJ
authors.lastname: Kalkwarf
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Daniels
mesh_terms: D001823:Body Composition; D015992:Body Mass Index; D015519:Bone Density; D002648:Child; D002675:Child, Preschool; D015438:Health Behavior; D006801:Humans; D016018:Least-Squares Analysis; D009765:Obesity / Q000517:prevention & control*; D013690:Television