Mothers can add higher child IQ to the list of benefits associated with breastfeeding: New research shows that the longer a new mom breastfeeds up to one year, the greater the benefit on her baby's intelligence.
Babies who were breastfed for the first year of life gained 4 points on their IQ, compared with babies who were not breastfed for as long, according to the findings, published online in JAMA Pediatrics. These children were better able to understand what others were telling them (receptive language) at three years and had higher verbal and non-verbal intelligence at seven years.
"These findings support national and international recommendations to promote exclusive breastfeeding through age six months and continuation of breastfeeding through at least age one 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 breastfeeding at six and 12 months. Children completed standard intelligence tests at age three years and seven years. Breastfed 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 breastfeeding 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 paediatrician at the Seattle Children's Hospital, said the new findings may motivate more women to breastfeed for longer periods of time. "There are some benefits of breastfeeding that have been very clearly shown," he said. These include reduced risk of diarrhoea, ear infections and eczema, a skin condition.
"The issue of the link between breastfeeding 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 breastfeed," he said.
"Four points at a population level means a lot," said Christakis, who also wrote an editorial accompanying the new study. "The problem is not so much that women don't start breastfeeding, it's that they don't sustain it," he said. Some go back to work after three months and may not want to breastfeed in public.
Stick with it
"It's time to start making it easier and more acceptable for women to breastfeed 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 breastfeeding.
"This new study indicates that independent of maternal intelligence and home environment that breastfeeding improves or increases a child's IQ," said Dr. Gail Herrine, an obstetrician at Temple University Health System in Philadelphia. When it comes to breastfeeding, "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 breastfeeding than others, and support is available, said Judy Fayre, a lactation consultant at Anna Jaques Hospital in Newburyport, Massachusetts. "If a new mother thinks she is unable to breastfeed, 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 breastfeeding.