MONDAY, July 29 (HealthDay News) -- Mothers can add higher child IQ to the list of benefits associated with breast-feeding: New research shows that the longer a new mom breast-feeds up to one year, the greater the benefit on her baby's intelligence.
Babies who were breast-fed for the first year of life gained 4 points on their IQ, compared with babies who were not breast-fed for as long, according to the findings, published online July 29 in JAMA Pediatrics. These children were better able to understand what others were telling them (receptive language) at 3 years and had higher verbal and nonverbal intelligence at 7 years.
"These findings support national and international recommendations to promote exclusive breast-feeding through age 6 months and continuation of breast-feeding through at least age 1 year," the study authors concluded.
For the study, researchers led by Dr. Mandy Belfort, of Boston Children's Hospital, followed more than 1,300 mothers and their children. Moms were asked about breast-feeding at 6 and 12 months. Children completed standard intelligence tests at age 3 years and 7 years. Breast-fed babies scored higher on these tests even when researchers controlled for other factors that may affect a child's IQ such as the mom's intelligence.
Belfort's team also looked at whether fish intake while breast-feeding had any bearing on childhood intelligence, but it did not seem to have a major effect. Some research had suggested that omega-3 fatty acids in fish may be important for infant brain development.
Dr. Dimitri Christakis, a pediatrician at the Seattle Children's Hospital, said the new findings may motivate more women to breast-feed for longer periods of time. "There are some benefits of breast-feeding that have been very clearly shown," he said. These include reduced risk of diarrhea, ear infections and eczema, a skin condition.
"The issue of the link between breast-feeding and intelligence has been hotly debated for a long time, and the promise of cognitive ability, educational achievement and what it may lead to may encourage more women to breast-feed," he said.
"Four points at a population level means a lot," said Christakis, who also wrote an editorial accompanying the new study. "The problem in the U.S. is not so much that women don't start breast-feeding, it's that they don't sustain it," he said. Some go back to work after three months and may not want to breast-feed in public.
"It's time to start making it easier and more acceptable for women to breast-feed for longer," Christakis added. Among other things, this includes baby-friendly workplaces and taking steps to make sure breast pumps are covered by insurance.
Other experts also voiced support for continued breast-feeding.
"This new study indicates that independent of maternal intelligence and home environment that breast-feeding improves or increases a child's IQ," said Dr. Gail Herrine, an obstetrician at Temple University Health System in Philadelphia. When it comes to breast-feeding, "more is certainly better depending on the mother's ability to continue," she said.
But other factors contribute to a child's intelligence, Herrine added.
Some women may have a harder time breast-feeding than others, and support is available, said Judy Fayre, a lactation consultant at Anna Jaques Hospital in Newburyport, Mass. "If a new mother thinks she is unable to breast-feed, speak to a lactation consultant or join a support group before giving up."
The American Academy of Pediatrics has more about the benefits associated with breast-feeding.