Zinc supplements reduce diarrhoea and other infections in malnourished children, and may prevent death, according to a new study published in The Cochrane Library. The study is the first Cochrane systematic review to focus on zinc as a means to prevent childhood death, including deaths caused by diarrhoea, one of the biggest killers of children under-five.
Zinc is a micronutrient with important roles in growth and in the immune, nervous and reproductive systems. The human body cannot make it, so it has to come from our diet. It is estimated that more than 1 in 6 people globally are deficient in zinc and that around 1 in every 58 deaths in children under five is related to zinc deficiency. Zinc deficiency is common in Pakistan, Southeast Asia, sub-Saharan Africa and parts of Latin America.
The authors were interested in whether zinc supplements could reduce childhood death and disease, and help support growth. They reviewed data from 80 trials involving 205,401 children aged six months to twelve years, mostly in low and middle income countries.
In Pakistan, the trials were conducted in Bilal Colony, Karachi and in Matiari in Sindh.
The findings indicated that those children who took zinc were less likely to suffer a bout of diarrhoea, and when the researchers looked at growth differences, they saw that children who were given zinc were slightly taller by the end of the trials compared to those who did not.
"We should remember that supplements are not a substitute for a well-balanced diet," said senior researcher Professor Zulfiqar Bhutta from the Centre of Excellence in Women and Child Health, Aga Khan University, Karachi, Pakistan, and Sick Kids Center for Global Child Health, Toronto, Canada. "However, in countries where zinc deficiency is common, supplements may help to reduce child deaths and related diseases in the short-term."
Overall, the authors, including Drs Zulfiqar Bhutta and Sohni Dean of AKU, concluded that zinc supplementation could benefit children as part of wider programmes to address public health and nutrition challenges in these countries.
In Pakistan, zinc needs to be part of diarrhoea treatment programmes countrywide. “While the combination of zinc and ORS and their effectiveness in treating diarrhoea are well known, this combination is not being widely used,” said Dr Aamer Imdad who had worked on this study while at AKU.
However, it must be understood that administering zinc alone is insufficient and healthy eating is more important for growth. "Eating foods with balanced energy and protein and multiple micronutrients would probably have a larger effect for many malnourished children," said Evan Mayo-Wilson, the lead author based at the Johns Hopkins University Bloomberg School of Public Health in Baltimore, Maryland.
Dr David Tovey, Editor-in-Chief, Cochrane, said, “Policymakers in low and middle income countries need evidence that directly addresses the needs of their own health services. This comprehensive review makes a very valuable contribution to the evidence base around interventions may make an important contribution to improving Global Health.”
For more information, read the review in The Cochrane Library.
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