title: [Relation of long-term consumption of school milk to bone density in children].
abstract: OBJECTIVE
  To evaluate the status of bone density of children consumed school milk for relative long-term period.
  
  
  METHODS
  According to the frequency and duration that children had consumed school milk, cluster sampling of 435 children (10-12 years old, including 188 boys and 247 girls.) were sampled to divided into two groups, that is milk consumption group and seldom milk consumption group, the children in milk consumption group had consumed the school milk 4 time weekly and duration for more than 1 year or 1-3 times weekly and duration for more than 3 years and this group included 220 children. Right forearm length, bone width of 1/3 distal end of radius and ulna, bone mineral content, bone density, serum calcium and phosphorus contents were determined. The research was carried out from July to August (2009) in Changsha, Hunan Province.
  
  
  RESULTS
  Right forearm length of the milk consumption group boys 22.53 cm +/- 1.63 cm) was significantly longer than that of seldom milk consumption group (21.95 cm+/- 1.75 cm, P < 0.05, radius width (1.37 +/- 0.237 cm) was significantly larger than that of seldom milk consumption group (1.300 cm +/- 0.176 cm), P < 0.05, bone mineral content (0.690 +/- 0.270) was significantly higher than that of seldom milk consumption group (0.599 +/- 0.090) , P < 0.01, bone density of radius (0.498 +/- 0.135) was significantly higher than that of seldom milk consumption group (0.469 +/- 0.081), P < 0.05. Bone density of radius of girls (0.489 +/- 0.076) was significantly higher than that of seldom milk consumption group (0.469 +/- 0.081), P < 0.05, bone mineral content of ulna (0.564 +/- 0.176) was significantly higher than that of seldom milk consumption group (0.512 +/- 0.100), P < 0.01, bone density of ulna (0.470 +/- 0.129) was significantly higher than that of seldom milk consumption group (0.439 +/- 0.059), P < 0.05. The state of children consumed school milk was correlative closely with type and characteristics of milk.
  
  
  CONCLUSIONS
  The long-term consumption of school milk could increase their bone density and the type and characteristics of milk would have effect on the practice and generalization of the school milk planning.
authors: Hunan Provincial Center for Disease Control and Prevention, Changsha 410005, China.
authors: Yuechan
authors: Y
authors: Zhou
authors: Yuming
authors: Y
authors: Hu
authors: Zheng
authors: Z
authors: Ma
authors: Xianfeng
authors: X
authors: Zhao
authors: Shi'an
authors: S
authors: Yin
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology*; D001842:Bone and Bones / Q000737:chemistry*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008892:Milk; D012494:Sampling Studies; D013334:Students