Zinc deficiency is generally predominant in children in developing countries. Zinc deficiency also plays a role in decreased immunity and increased risk of infection. Preventive zinc supplementation in healthy children can decrease the mortality because of common causes like diarrhoea, malaria and pneumonia. The aim of this study is to evaluate the all-cause mortality and cause-specific mortality and morbidity in children who are under five years of age in developing countries for preventive zinc supplementation.

A literature search had been carried out on the Cochrane Library, PubMed, and the WHO regional databases to detect RCTs on zinc supplementation for more than 3 months in children < 5 years of age in developing countries and its outcome on mortality was analysed.

The outcomes of preventive zinc supplementation on mortality was observed in eight trials, whereas the cause specific mortality evidence was reported in 5 out of these eight trials. Zinc supplementation was associated with a statistically insignificant 9% reduction in all-cause mortality in the intervention group as compared to the control group by using a random effect model. The effect on diarrhoea-specific mortality of zinc alone was 18% reduction and 15% reduction for pneumonia-specific mortality. The occurrence of diarrhoea exhibited a 13% reduction with preventive zinc supplementation and a 19% reduction in pneumonia morbidity.

The effect of zinc supplementation in reducing diarrhoea and pneumonia related morbidity and mortality was considered in all the outcomes for selection of efficacy estimate for inclusion in the LiST model. Thus, it was concluded that zinc supplementation in children is associated with a decrease in diarrhoea mortality by 13% and pneumonia mortality by 15% for inclusion in the LiST tool. No effect was observed in malaria specific mortality.

Source: Yakoob MY, Theodoratou E, Jabeen A, Imdad A, Eisele TP, Ferguson J, Jhass A, Rudan I, Campbell H, Black RE, Bhutta ZA. Preventive zinc supplementation in developing countries: impact on mortality and morbidity due to diarrhea, pneumonia and malaria. BMC Public Health. 2011 Apr 13;11 Suppl 3(Suppl 3):S23. doi: 10.1186/1471-2458-11-S3-S23. PMID: 21501441; PMCID: PMC3231897.