Review: Zinc to prevent respiratory tract infections
Zinc supplementation is a potential option to prevent acute lower respiratory infection, especially in developing countries.
Researchers at The Johns Hopkins Bloomberg School of Public Health, in Baltimore, Maryland make sense of the discrepant research findings.
First, the details.
- 10 studies of zinc supplementation in 49,450 children in developing countries were identified.
- Studies in the meta-analysis included participants less than 5 years of age, taking daily/weekly zinc vs a control supplementation for greater than 3 months.
- Acute lower respiratory infections were classified on the basis of specificity/severity.
And, the results.
- Routine zinc supplementation (at least 70 mg cumulative dose per week, for 43 months) reduced the risk of childhood acute lower respiratory infection by about one-third.
- Investigators’ definitions of acute lower respiratory infection may have influenced the results regarding the value of preventive treatment.
- There were no associations with the average age of participants, geographic location, participants’ nutritional status (prevalence of stunting or zinc blood levels), or zinc dose.
The bottom line?
The authors concluded, “Routine zinc supplementation reduced the incidence of childhood acute lower respiratory infection defined by relatively specific clinical criteria.”
10/5/11 22:20 JR