Multimicronutrient interventions but not vitamin a or iron interventions alone improve child growth: results of 3 meta-analyses.
Meta-analyses of randomized controlled intervention trials were conducted to assess the effects of vitamin A, iron, and multimicronutrient interventions on the growth of children < 18 y old. A PubMed database search and other methods identified 14 vitamin A, 21 iron, and 5 multimicronutrient intervention studies that met the design criteria. Weighted mean effect sizes and CI were calculated using a random effects model for changes in height and weight. Tests for homogeneity and stratified analyses by predefined characteristics were conducted. Vitamin A interventions had no significant effect on growth; effect sizes were 0.08 (95% CI: -0.20, 0.36) for height and -0.01 (95% CI: -0.24, 0.22) for weight. Iron interventions also had no significant effect on child growth. Overall effect sizes were 0.09 (95% CI: -0.07, 0.24) for height and 0.13 (95% CI: -0.05, 0.30) for weight. The results were similar across categories of age, duration of intervention, mode and dosage of intervention, and baseline anthropometric status. Iron interventions did result in a significant increase in hemoglobin (Hb) concentrations with an effect size of 1.49 (95% CI: 0.46, 2.51). Multimicronutrient interventions had a positive effect on child growth; the effect sizes were 0.28 (95% CI: 0.16, 0.41) for height and 0.28 (95% CI: -0.07, 0.63) for weight. Interventions limited to only vitamin A or iron did not improve child growth. Multimicronutrient interventions, on the other hand, improved linear and possibly ponderal growth in children.
Department of International Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA. uramakr@sph.emory.edu
Usha
U
Ramakrishnan
Nancy
N
Aburto
George
G
McCabe
Reynaldo
R
Martorell
D000349:Africa; D001208:Asia; D001827:Body Height / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D006128:Growth / Q000187:drug effects*; D006801:Humans; D007223:Infant; D007501:Iron / Q000494:pharmacology*; D018977:Micronutrients / Q000494:pharmacology*; D016032:Randomized Controlled Trials as Topic; D014801:Vitamin A / Q000494:pharmacology*; D015430:Weight Gain / Q000187:drug effects
D018977:Micronutrients; D014801:Vitamin A; D007501:Iron