Breastfed Babies Aren't Smarter
But Researchers Say There Are Still Lots of Good Reasons for Breastfeeding
Oct. 3, 2006 -- Do breastfed babies become brainier kids? Some studies say
yes, but new research shows no direct link between breastfeeding and
intelligence later in life.
In the largest study ever to address the issue, researchers found a positive
impact for breastfeeding on intelligence only when other potential contributors
-- such as the mother's IQ and the parents' educational and economic status --
were not taken into consideration.
When these variables were considered, breastfeeding was found to have little
impact on a child's IQ.
The study included 5,475 children and mothers in the U.S. who participated
in an ongoing youth development survey. The findings were published today in
BMJ Online First.
The researchers also identified 332 sibling pairs in which one child was
breastfed and the other was not. No significant difference in intelligence was
found among the breastfed and nonbreastfed siblings.
"The mother's IQ was by far the most important variable, accounting for
70% to 75% of the difference [between children who were and were not
breastfed]", researcher Geoff Der, MCS, tells WebMD.
The first study linking breastfeeding to greater intelligence later in life
appeared almost 80 years ago. But the research since that time has been
"Although the majority of studies concluded that breastfeeding promotes
intelligence, the evidence from higher quality studies is less persuasive,"
researcher Anjali Jain, MD, and colleagues wrote in 2002 in the journal
When Der and colleagues combined their own results with those from other
studies that also considered maternal intelligence, they again found little
evidence of a link between breastfeeding and intelligence.
"We took three different approaches to examining this question within
this one paper, and the results converged quite nicely," Der says.
Breastfeeding Still Best
Der and colleagues from the British research group Medical Research Council
expressed surprise that maternal intelligence has been overlooked in so many
studies examining the impact of breastfeeding on intelligence. Even many recent
studies have failed to consider maternal IQ.
They add that the latest findings should not be interpreted as meaning that
new moms now have less reason to breastfeed.
"Even if it does not enhance intelligence, breastfeeding remains an
unequalled way of providing ideal food for the healthy growth and development
of infants," they write.
Breastfeeding has been shown to lower an infant's risk of infections and
even sudden infant death syndrome (SIDS), and it is believed to help protect
against allergies, diabetes, and obesity later in life.
"We would never suggest that any woman should choose not to breastfeed
on the basis of our findings," Der says. "Clearly, there are many good
reasons to breastfeed."