"We found that more than one-half of the estimated effect of being breast-fed on high school grades can be linked to improvements in cognitive ability and health," Sabia said. "Thus, we conclude that improvements in cognitive ability and adolescent health may be important pathways through which breast-feeding affects long-term academic achievement," he said.
About one-fifth of the increased likelihood of going to college appears to be due to breast-feeding, Rees added.
"This is another benefit of breast-feeding," Rees said. "We know that breast-feeding leads to better health, higher IQ, but the next step is what are the implications, and this is an important implication," he said.
Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine, said this study may not prove a connection between school performance and breast-feeding, but it could be another reason to breast-feed your baby.
"An array of health benefits is convincingly associated with breast-feeding, including a reduced risk of both infections and obesity in the breast-fed child," Katz said. "Less certain, but long suggested, is enhanced cognitive development in breast-fed children as well."
It could be that factors that determine whether or not a baby is breast-fed are an important piece of the puzzle, Katz noted. "Why a baby is fed one way or another may matter as much as which way a baby is fed," he said. "A study of association such as this cannot fully resolve that issue."
For more on breast-feeding, visit the U.S. National Library of Medicine.
SOURCES: Joseph Sabia, Ph.D., assistant professor, public policy, American University, Washington, D.C.; Daniel Rees, Ph.D., professor, economics, University of Colorado Denver; David L. Katz
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