Zinc can combat childhood killers

Part of the research was carried out in Bangladesh

Zinc supplements can help prevent children in developing countries from contracting two of the biggest killer diseases - pneumonia and diarrhoea, say researchers.

Giving children zinc, either in tablet form as a food additive, could save lives, according to Robert Black and Sunil Sazawal, of the Johns Hopkins School of Public Health in Baltimore.

This effect is greater than that estimated for any other intervention to prevent pneumonia

Johns Hopkins School of Public Health scientists

The two scientists analysed ten different studies of zinc supplements.

They found that adding the mineral to a child's diet for as short a period as two weeks could reduce pneumonia episodes by 41% and diarrhoea by 25%.

Writing in the Journal of Pediatrics, they say: "This effect is greater than that estimated for any other intervention to prevent pneumonia."

They said the result was not unexpected because malnutrition was known to increase a child's risk of disease.

Zinc deficiency

"Zinc deficiency impairs many cellular and humoral (involving hormones and similar compounds) immune functions including lymphocyte number and function."

Zinc facts

Dietary sources include meat, milk, cereals, eggs and pusles

Zinc deficiency occurs when the diet is based on unrefined cereals that block the mineral being absorbed into the body

Zinc play a role in growth, the immune system and wound healing

Working with the World Health Organization, the researchers pooled reports on zinc supplements given to children in India, Mexico, Papua New Guinea, Peru, Vietnam, Guatemala, Jamaica, Bangladesh and Pakistan.

Pooling smaller studies increases the power of the research, providing enough numbers to produce a more meaningful result.

Sara Stanner, a nutrition scientist for the British Nutrition Foundation, said the research was "interesting".

She said: "We know that zinc is involved in the immune system and therefore has effects.

"There is also some evidence to suggest that giving zinc to pregnant women helps prevent low birth weight."

Dr Stanner said vitamin A had been shown to have similar therapeutic effects.