A community-based randomized controlled trial of iron and zinc supplementation in Indonesian infants: effects on growth and development.
BACKGROUND
Deficiencies of iron and zinc are associated with delayed development, growth faltering, and increased infectious-disease morbidity during infancy and childhood. Combined iron and zinc supplementation may therefore be a logical preventive strategy.


OBJECTIVE
The objective of the study was to compare the effects of combined iron and zinc supplementation in infancy with the effects of iron and zinc as single micronutrients on growth, psychomotor development, and incidence of infectious disease.


METHODS
Indonesian infants (n = 680) were randomly assigned to daily supplementation with 10 mg Fe (Fe group), 10 mg Zn (Zn group), 10 mg Fe and 10 mg Zn (Fe+Zn group), or placebo from 6 to 12 mo of age. Anthropometric indexes, developmental indexes (Bayley Scales of Infant Development; BSID), and morbidity were recorded.


RESULTS
At 12 mo, two-factor analysis of variance showed a significant interaction between iron and zinc for weight-for-age z score, knee-heel length, and BSID psychomotor development. Weight-for-age z score was higher in the Zn group than in the placebo and Fe+Zn groups, knee-heel length was higher in the Zn and Fe groups than in the placebo group, and the BSID psychomotor development index was higher in the Fe group than in the placebo group. No significant effect on morbidity was found.


CONCLUSIONS
Single supplementation with zinc significantly improved growth, and single supplementation with iron significantly improved growth and psychomotor development, but combined supplementation with iron and zinc had no significant effect on growth or development. Combined, simultaneous supplementation with iron and zinc to infants cannot be routinely recommended at the iron-to-zinc ratio used in this study.
Lind
Torbjörn
T
Department of Public Health and Clinical Medicine, Epidemiology and Public Health Sciences, Umeå University, SE-901 87 Umeå, Sweden. torbjorn.lind@epiph.umu.se
Lönnerdal
Bo
B
Stenlund
Hans
H
Gamayanti
Indria L
IL
Ismail
Djauhar
D
Seswandhana
Rosadi
R
Persson
Lars-Ake
LA
D018798:Anemia, Iron-Deficiency / Q000150:complications / Q000517:prevention & control*; D002657:Child Development / Q000187:drug effects*; D003153:Community Health Services; D019587:Dietary Supplements; D004311:Double-Blind Method; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005163:Factor Analysis, Statistical; D005260:Female; D006128:Growth / Q000187:drug effects*; D006801:Humans; D007214:Indonesia; D007223:Infant; D007501:Iron / Q000008:administration & dosage* / Q000627:therapeutic use; D008297:Male; D010919:Placebos; D011597:Psychomotor Performance / Q000187:drug effects; D015032:Zinc / Q000008:administration & dosage* / Q000172:deficiency* / Q000627:therapeutic use
D010919:Placebos; D007501:Iron; D015032:Zinc