Mother's milk and sewage: their interactive effects on infant mortality.

If they lived in households without piped water or a toilet, Malaysian infants who did not breast-feed were five times more likely to die after 1 week of age than those who breast-fed, when other significant factors affecting infant mortality were taken into account. This is double the relative risk associated with not breast-feeding for infants born into households with toilets, whether or not they had piped water. Analogously, improvements in...