title: [Effects of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis].
abstract: OBJECTIVE
  To evaluate the effect of vitamin A, vitamin A plus iron and "7 + 1" multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis in preschool children.
  
  
  METHODS
  This was a randomized, controlled and blinded interventional field trial. A total of 226 2 - 7 years old preschool children were recruited from three nurseries in the area, and they were randomly assigned into three different fortified diet groups for 6 months. The subjects in Group I were fortified with vitamin A; those in Group II and III were fortified with vitamin A plus iron and vitamin A plus iron, thiamine, riboflavin, folic acid, niacinamide, zinc and calcium (7 + 1), respectively. The concentration of serum vitamin A was measured by high-performance liquid chromatography (HPLC), serum ferritin (SF) was measured by enzyme-linked immunosorbent assay (ELISA), soluble transferrin receptor (sTfR) was measured by microparticle-enhanced, and hemoglobin (HB) by hemiglobincyanide, the sTfR-SF index (TFR-F index) and total body iron content were computed respectively before and after intervention. Simultaneously, children's demographic data, socio-economic status and eating habits, etc. were investigated by questionnaires.
  
  
  RESULTS
  A total of 226 preschool children were included in the study with age ranged from 2 to 7 years with average age (4.0 ± 0.85) (means ± standard deviation). The prevalence of anemia, deficient iron storage, vitamin A deficiency (VAD) and suspect sub-clinical vitamin A deficiency (SSVAD) were 23.5%, 15.0%, 6.3% and 25.9%, respectively. The levels of SF and sTfR significantly decreased after intervention in all groups (χ(2) = 8.3298, χ(2) = 16.1471, χ(2) = 15.1371, χ(2) = 15.1171, χ(2) = 5.2617, χ(2) = 4.8844, P < 0.05) especially in group II and group III for SF (χ(2) = 16.1471, χ(2) = 15.1371, P < 0.05) and group I for sTfR (χ(2) = 15.1171, P < 0.05). No marked change of TFR-F index and total body iron contents was observed in group I (t = 0.1817, t = 1.7736, P > 0.05), while TFR-F index decreased and total body iron contents increased in group II and group III (t = 5.3561, t = 6.5979, t = 11.1663, t = 8.7306, P < 0.05) after intervention.
  
  
  CONCLUSIONS
  Vitamin A intervention has significant effect on iron storage and mobilization but seldom effect on iron absorption in small intestine. The combination of vitamin A and other micronutrients might be a better intervention for the improvement of iron deficiency for preschool-children.
authors.affiliation: Children's Nutrition Research Center, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Chen
authors.forename: Yong-fang
authors.initials: YF
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.forename: You-xue
authors.initials: YX
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Ting-yu
authors.initials: TY
authors.lastname: Li
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000517:prevention & control; D002648:Child; D002675:Child, Preschool; D005260:Female; D005527:Food, Fortified; D006801:Humans; D007501:Iron / Q000378:metabolism*; D000090463:Iron Deficiencies; D008297:Male; D018977:Micronutrients / Q000627:therapeutic use*; D014801:Vitamin A / Q000627:therapeutic use*
chemical_list: D018977:Micronutrients; D014801:Vitamin A; D007501:Iron