The longer babies are nursed the smarter they are, and every month makes a difference.
For each additional month of breastfeeding the child's language abilities were increased at three years old and they had higher intelligence at the age of seven, Bloomberg reported.
Researchers observed the development of over 1,000 women's children from pre-birth to the age of seven. They found the children's IQ improved by one-third of a point for every additional month they had breastfed. There seemed to be even more of a benefit if the mother had eaten fish during the breastfeeding period.
"With this we can close the book and decide there is a link between child breastfeeding and intelligence," Dimitri Christakis, a professor of pediatrics at Seattle Children's Research Institute, a pediatric medical research center, said. "The fact that breastfeeding really promotes cognition in our children is something we should all care about. It takes a village to breastfeed a child. We should take the actions necessary not to just initiate breastfeeding but to sustain it."
Mandy Belfort, lead author of the study, warned breastfeeding is not the only contributing factor to intelligence.
"It's important to point out that breastfeeding is just one factor that influences a child's intelligence," Belfort said. "Our results shouldn't make parents feel bad for the choice they have made."
The researchers saw a correlation between breastfeeding and brains, but are unsure of how or why breast milk affects intelligence.
"There are nutrients in breast milk that don't really exist anywhere else, and we don't fully know why," Christakis told The Wall Street Journal.
The Centers for Disease Control and Prevention (CDC) recommends babies breastfeed until the age of six months, then some basic food can be introduced. The CDC believes children should breastfeed until they are at least a year old, Bloomberg reported.
The researchers hope this study will promote healthy breastfeeding habits between mothers and their children.
"Individual women should use this as one further incentive to breastfeed their children," Christakis said.
