title: [Influence of diet behaviors on height among children and adolescents in China: a multiple level analysis].
abstract: OBJECTIVE
  To categorize growth and development stages among children and adolescents based on height, and to explore the influences of diet behaviors on height during different growth and development stages.
  
  
  METHODS
  Children and adolescents (7 to 18 years) with normal weights were selected using "Reference Norm for Screening Overweight and Obesity in Chinese Child and Adolescent" set up by WGOC in 2003 and "Reference Norm for Screening Underweight in Chinese Child and Adolescent" from the "2010 National Physical Fitness and Health Surveillance" data, and the variables of height and diet behaviors sorted. The growth and development stages were categorized using the hierachical cluster analysis, and the multilevel model was used to analyze influences of diet behaviors on height at different growth and development stages.
  
  
  RESULTS
  Basis on height, there were 4 growth and development stages among the children and adolescents. In the boys, growth and development stages included Pre-GSS (growth spurt stage, GSS) including 7 to 10 years, GSS (11 to 12 years), Post-GSS (13 to 14 years), and growth stability stage (15 to 18 years); in the girls, the stages included the fast velocity GS (growth stage, GS) including 7 to 10 years, GS (11 to 12 years), Post-GS (13 to 15 years), and growth stability stage (16 to 18 years). The results of the multilevel model showed that the students' height in the urban areas were higher than in the rural areas (P<0.01), and the trend of difference between the urban and rural areas with the different growth stages was a parabola shape, the highest differences were 3.36 cm and 3.23 cm in the GSS and the fast velocity GS, respectively. There were significant influences of breakfast on height during the Pre-GSS and the fast velocity GS (P<0.01), and increased 0.40 cm and 0.57 cm, respectively. Excluding the stablility growth stage in the girls, drinking milk increased significantly height during the different growth stages (P<0.01), and the increases were gradual downtrend with the growth stages, the highest increase was 0.91 cm and 0.94 cm in Pre-GSS and the fast velocity GS, respectively. Eating eggs increased significantly height during all the growth stages (P<0.01), and the increases were the gradual uptrend with different growth stages. There were interaction effects among breakfast, drinking milk and eating eggs during the different growth stages, which was the gradual downtrend.
  
  
  CONCLUSIONS
  Breakfast and drinking milk are conducive to growth during early adolescence, and the effect of eating eggs on growth is gradual uptrend with different growth stages.
authors.affiliation: Department of Child, Adolescent and Women's Health, Peking University School of Public Health, Beijing, China.
authors.forename: Lian-guo
authors.initials: LG
authors.lastname: Fu
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.forename: Hai-jun
authors.initials: HJ
authors.lastname: Wang
authors.forename: Pei-jin
authors.initials: PJ
authors.lastname: Hu
authors.forename: Yi
authors.initials: Y
authors.lastname: Song
authors.forename: Jia-shuai
authors.initials: JS
authors.lastname: Liu
authors.forename: Zi-long
authors.initials: ZL
authors.lastname: Zhang
authors.forename: Xiao-rui
authors.initials: XR
authors.lastname: Shang
authors.forename: Yi-de
authors.initials: YD
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000818:Animals; D044466:Asian People; D001827:Body Height; D002648:Child; D002681:China; D004032:Diet; D004531:Eggs; D005260:Female; D006801:Humans; D008297:Male; D008892:Milk; D015233:Models, Statistical; D055361:Multilevel Analysis; D013334:Students