Zinc May Help Prevent Childhood Diarrhea, Pneumonia
Zinc deficiency is common among children, even in developing countries, and has been associated with an elevated risk of compromised immunity and infectious disease.
This study evaluated the influence of zinc supplementation on diarrhea and pneumonia by analyzing results from 10 randomized, controlled trials on children in nine developing countries.
The trials were of two types: those in which supplements were provided for the entire period ("continuous supplementation trials"), and those in which supplements were given for a short period (two weeks) followed by monitoring for the incidence of disease ("short-course trials").
Seven continuous and three short-course trials were included in the analysis. In the first set of trials, zinc supplementation was provided at 1-2 times the recommended daily allowance (RDA) 5-7 times per week. In the second set of trials, zinc supplementation amounted to 2-4 times the RDA daily for two weeks, followed by 2-3 months of surveillance for incidence of diarrhea and/or pneumonia. Results are presented below:
Zinc supplementation resulted in a reduced relative risk for diarrhea (0.82) and pneumonia (0.59).
Zinc supplementation also reduced the relative risk for diarrhea (0.89) and pneumonia (0.74).
These findings provide evidence that "zinc supplementation in children in developing countries is associated with substantial reductions in the rates of diarrhea and pneumonia, the two leading causes of death in these settings." The authors recommend the development of effective interventions to ensure adequate zinc status, especially in these populations.
Bhutta ZA, Black RE, Brown KH, et al. Prevention of diarrhea and pneumonia by zinc supplementation in children in developing countries: pooled analysis of randomized controlled trials. Journal of Pediatrics