Breast-feeding has many advantages, and a study by the National Institute of Environmental Health Sciences gives one more reason to choose the natural option at mealtime.

What the researchers wanted to know: There's good evidence that breast-fed babies are less likely to get sick. Does breast-feeding also decrease the risk of dying?

What they did: Epidemiologists at the National Institute of Environmental Health Sciences analyzed data from the 1988 U.S. National Maternal and Infant Health Survey. Mothers of babies who survived and babies who died were included in the survey. The mail survey asked mothers whether they had breast-fed their babies and, if they had, for how long. The researchers looked only at the chance of dying between 4 weeks and 1 year of age, because most infants who die before 4 weeks die of congenital defects or because they were premature. The researchers also excluded deaths from congenital defects that happened later.

What they found: Babies who were breast-fed longer had a lower risk of dying. Even among the babies who died, those who were ever breast-fed lived slightly longer. Comparing the two groups, only 38 percent of infants who died had been breast-fed, compared with 53 percent of the infants who did not die. This information is a little surprising, because breast-feeding protects best against infectious diseases, and babies are less likely to die of infectious diseases than they used to be.

What this study means to you: This is another piece of evidence that breast-feeding is good for babies' health.

Caveats: Infant mortality has fallen since 1988, when the babies studied here were born. Also, it's not clear that persuading a mother to breast-feed will help her baby—it may be that breast-feeding is just one part of a package of mothering skills that all come together, so increasing breast-feeding may not help without also improving other factors. Another possibility is that some of the babies who died were too sick to breast-feed. And, finally, the survey depends on mothers reporting their breast-feeding accurately.

Find out more: The American Academy of Pediatrics, which published the journal this article appears in, has information for mothers about breast-feeding.

Breast-feeding from the Centers for Disease Control and Prevention: http://www.cdc.gov

The World Health Organization's information on infant and child feeding and nutrition: http://www.who.int/

Read the article: Chen, A., and W.J. Rogan. "Breastfeeding and the Risk of Postneonatal Death in the United States." Pediatrics. May 2004, Vol. 113, No. 5, pp. e435–e439.