Study touts benefits of breast-feeding
Researchers link the practice to higher child IQ
By Will Dunham, Reuters | May 6, 2008
WASHINGTON - A new study provides some of the best evidence to date
that breast-feeding can make children smarter, an international team
of researchers said yesterday.
Children whose mothers breast-fed them longer and did not mix in baby
formula scored higher on intelligence tests, researchers in Canada and
Belarus reported.
About half the 14,000 babies were randomly assigned to a group in
which prolonged and exclusive breast-feeding by the mother was
encouraged at Belarusian hospitals and clinics. The mothers of the
other babies received no special encouragement.
Those in the breast-feeding encouragement group were, on average,
breast-fed longer than the others and were less likely to have been
given formula in a bottle.
At 3 months, 73 percent of the babies in the breast-feeding group were
breast-fed, compared with 60 percent of the other group. At 6 months,
it was 50 percent versus 36 percent.
In addition, the group given encouragement was far more likely to give
their children only breast milk. The rate was seven times higher, for
example, at 3 months.
The children were monitored for about 6 1/2 years.
The children in the group where breast-feeding was encouraged scored
about 5 percent higher in IQ tests and did better academically,
researchers found.
Previous studies had indicated brain development and intelligence
benefits for breast-fed children.
But researchers have sought to determine whether the benefits were
because the children were breast-fed, or that mothers who prefer to
breast-feed their babies may differ from those who do not.
The design of the study - randomly assigning babies to two groups
regardless of the mothers' characteristics - was intended to eliminate
the confusion.
"Mothers who breast-feed or those who breast-feed longer or most
exclusively are different from the mothers who don't," Dr. Michael
Kramer of McGill University in Montreal and the Montreal Children's
Hospital said in a phone interview.
"They tend to be smarter. They tend to be more invested in their
babies. They tend to interact with them more closely. They may be the
kind of mothers who read to their kids more, who spend more time with
their kids, who play with them more," added Kramer, who led the study
published in the journal Archives of General Psychiatry.
Researchers measured the differences between the two groups using IQ
tests administered by the children's pediatricians and by ratings by
their teachers of their school performance.
Both sets of scores were significantly higher in the children from the
breast-feeding promotion group.
The study was launched in the mid-1990s. Kramer said the initial idea
was to do it in the United States and Canada, but many hospitals in
those countries by that time had begun strongly encouraging breast-
feeding as a matter of routine.
The situation was different in Belarus at the time, he said, with less
routine encouragement for the practice.
Kramer said that how breast-feeding may make children more intelligent
is unclear.
"It could even be that because breast-feeding takes longer, the mother
is interacting more with the baby, talking with the baby, soothing the
baby," he said. "It could be an emotional thing. It could be a
physical thing. Or it could be a hormone or something else in the milk
that's absorbed by the baby."
Previous studies have shown that babies whose mothers breast-fed them
enjoy many health advantages over formula-fed babies.
These include fewer ear, stomach, or intestinal infections, digestive
problems, skin diseases and allergies, and less risk of developing
high blood pressure, diabetes, and obesity.
The American Academy of Pediatrics recommends that women who do not
have health problems exclusively breast-feed their infants for at
least the first six months, and continue to breast-feed at least
through the first year as other foods are introduced.
Study links breast-feeding to higher IQ scores for children - The
Boston Globe
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