Effect of zinc supplementation between 1 and 6 mo of life on growth and morbidity of Bangladeshi infants in urban slums
Osendarp, S.J.M.; Santosham, M.; Black, R.E.; Wahed, M.A.; van Raaij, J.M.A.; Fuchs, G.J.
American Journal of Clinical Nutrition 76(6): 1401-1408
2002
ISSN/ISBN: 0002-9165 PMID: 12450909 DOI: 10.1093/ajcn/76.6.1401Document Number: 262124
Background: Evidence for an effect of zinc supplementation on growth and morbidity in very young infants in developing countries is scarce and inconsistent. Objective: We assessed the effect of zinc supplementation on growth and morbidity in poor infants aged 4-24 weeks in Bangladesh. Design: Between April and June 1997, infants from Dhaka slums were enrolled at 4 weeks of age and randomly assigned to receive 5 mg elemental Zn/day (n=152) or placebo (n=149) until 24 weeks of age. They were followed weekly for information on compliance and morbidity; anthropometric measurements were performed monthly. Serum zinc was assessed at baseline and at 24 weeks of age. Results: At age 24 weeks, serum zinc concentrations were higher in the zinc than in the placebo group (13.3+or-3.8 and 10.7+or-2.9 micro mol/litre, respectively; P<0.001). Significantly greater weight gains were observed in the zinc than in the placebo group for 43 infants who were zinc deficient (<9.18 micro mol/litre) at baseline (3.15+or-0.77 and 2.66+or-0.80 kg, respectively; P<0.04). In the other infants, no significant differences were observed in mean weight and length gains during the study period. Zinc-deficient infants showed a reduced risk of incidence of acute lower respiratory infection after zinc supplementation (relative risk: 0.30; 95% CI: 0.10, 0.92); among the non-zinc-deficient infants there were no significant differences between treatment groups. Conclusions: Zinc-deficient Bangladeshi infants showed improvements in growth rate and a reduced incidence of acute lower respiratory infection after zinc supplementation. In infants with serum zinc concentrations >9.18 micro mol/litre, supplementation improved only biochemical zinc status.