Those results, to be published online Monday in the journal Pediatrics, are only an estimate. But several experts who reviewed the analysis said the methods and conclusions seemed sound.
"The healthcare system has got to be aware that breast-feeding makes a profound difference," said Dr. Ruth Lawrence, who heads the American Academy of Pediatrics' breast-feeding section.
The findings suggest that there are hundreds of deaths and many more costly illnesses each year from health problems that breast-feeding could help prevent. These include stomach viruses, ear infections, asthma, juvenile diabetes, sudden infant death syndrome and childhood leukemia.
The magnitude of health benefits linked to breast-feeding is vastly underappreciated, said lead author Dr. Melissa Bartick, an internist and instructor at Harvard Medical School. Breast-feeding is sometimes considered a lifestyle choice, but Bartick calls it a public health issue.
Among the benefits: Breast milk contains antibodies that help babies fight infections; it also can affect insulin levels in the blood, which may mean breast-fed babies are less likely to develop diabetes and obesity.
The analysis studied the prevalence of 10 common childhood illnesses, costs of treating those diseases, including hospitalization, and the level of disease protection other studies have linked with breast-feeding.
About $13 billion in losses from the current breast-feeding rate includes a calculation by economists based partly on lost potential lifetime wages -- $10.56 million for each death.
The methods were similar to a widely cited 2001 government report that said $3.6 billion could be saved each year if 50% of mothers breast-fed their babies for six months. Medical costs have climbed since then, and breast-feeding rates have increased only slightly.
About 43% of U.S. mothers do at least some breast-feeding for six months, but only 12% follow government guidelines recommending that babies receive only breast milk for six months.