Goldin found one study that concluded breast milk in the developed world could reduce a baby's overall risk of death. But after comparing statistics, she found that risk of death was equivalent to the risk parents take by driving with a child in a car.
"The risk of death that could be attributed to not nursing was equivalent to the risk of regular driving for a year with your child appropriately restrained," said Goldin. "So ... you should throw away the car? You need to walk everywhere?"
Still, Lawrence asserted that research on breast-feeding -- including research on IQ and immunity -- is largely conclusive.
"Every single baby saves the health care system $450 a year in health care costs is saved by breast-feeding," said Lawrence. "The science is good."
At least Goldin and Lawrence agreed that breast-feeding is a very difficult behavior to study.
"You can't do a blinded placebo control trial: You can't say to one woman, you breast-feed, and another, now you don't," said Lawrence. "It's not like having a cage full of mice."