Zinc during pregnancy prevents infantile diarrhoea

Giving pregnant women zinc supplements helps reduce diarrhoea-related illness in their babies.

Millions of children in the developing world suffer from diarrhoeal diseases, which can be life threatening. Zinc deficiency increases the risk of death due to diarrhoea, as well as pneumonia, malaria and other infectious diseases. Past studies have shown that giving zinc supplements to young children helps in treating their diarrhoea. The World Health Organization now recommends zinc supplementation in combination with rehydration therapy in the treatment of acute diarrhoea. However, little is known about the period before birth when zinc could potentially be most influential in later immune functioning.

To test whether zinc supplementation during pregnancy would reduce diarrhoeal illness in infants, researchers made a total of 214 Peruvian women take a daily supplement containing 15 milligrams zinc, 60 milligrams iron and 250 micrograms folic acid, while 207 matched control women took a similar-looking placebo supplement containing only iron and folic acid. About 420 infants of these women were followed up for illness. From the ages of 6 months to 1 year, 80 percent of the infants had at least one bout of diarrhoea, with a range of 0 to 11 episodes.

It was found that infants whose mothers took zinc while pregnant were sick about 5 percent of the days they were observed, whereas infants whose mothers took placebo were sick for around 8 percent of observation days. In addition, infants of zinc supplemented mothers were about 35 percent less likely to have an episode of diarrhoea lasting more than a week or to have mucus in the stool - a sign of more severe diarrhoea. There was also some evidence of a reduction in cases of the skin disease scabies in infants whose mothers took zinc.