Zinc Reduces Pneumonia, Diarrhea In Children In Developing Countries
WebMD News Archive
Dec. 7, 1999 (Los Angeles) -- A new report shows that zinc supplementation
substantially lowers the occurrence of diarrhea and pneumonia, the leading
causes of child death in the developing world. And although the study deals
primarily with developing nations, it has relevance for Americans, according to
one of its co-authors.
"Just because we get adequate calories does not necessarily mean that
our [intake of vitamins and minerals] is sufficient," explains Robert E.
Black, MD, MPH, a co-author and one of the coordinators of the report. "In
fact, several studies in the U.S. and Europe have documented mild to moderate
zinc deficiency in some populations. These same studies also showed positive
effects of zinc supplementation." The paper, published in the latest issue
of the Journal of Pediatrics, presents the results of analyses from 10
studies in nine developing nations.
Black tells WebMD, "The effect of zinc supplementation on the prevention
of diarrhea that we found compares favorably with other preventive measures,
including clean water, sanitation, or breast feeding, and zinc has a greater
preventive effect for pneumonia than any other current effort."
Black and his colleagues researched past studies in the area of vitamin and
mineral nutrition. To be eligible for inclusion in the study, a trial had to
include at least half the U.S. recommended daily allowance for zinc in
In all there were seven continuous trials in which the supplements were
given over the entire study period, and three "short-course" trials, in
which supplements were given for two weeks. In general, the children in the
short-course trials were not as well-nourished as the children in the
Zinc supplementation reduced the occurrence of diarrhea by up to 25%, an
effect the researchers described as "substantial and consistent," and
which compares favorably with other steps taken to reduce diarrhea, such as
improved sanitation and vitamin supplementation. The incidence of pneumonia was
reduced by 41%, an effect greater than that estimated for any other form of
This analysis, says Black, who teaches at the Johns Hopkins School of
Medicine in Baltimore, "was one important step necessary to move zinc into
child health programs around the world. We currently have a large-scale trial
in place to determine zinc's effect on child mortality. An earlier trial in low
birth-weight babies showed that zinc reduced their mortality by 34%."
Despite the fact that many products in U.S. markets, such as cereal, are
fortified with zinc, Black says there is still a need for doctors to emphasize
the importance dietary zinc. "The take-home message for doctors in the U.S.
is for them always to consider patients' nutritional status when treating them
for conditions that may seem unrelated, such as infectious diseases."