Numerous studies have concluded that children who were breastfed score higher on IQ tests and perform better in school.

Why would that be? Is it the mother-baby bonding time, something in breast milk or other attributes of families that have mothers who breastfeed their babies?

Sociologists from Brigham Young University think they have the answer and pinpoint two sources of this cognitive boost: Responding to children's emotional cues and reading to children starting at 9 months of age. Breastfeeding mothers tend to do both of those things, said lead author Ben Gibbs. 

So it's not the milk, it's the parenting, Gibbs says. "Breastfeeding matters in others ways, but this actually gives us a better mechanism and can shape our confidence about interventions that promote school readiness."

According to the analysis by Gibbs and fellow BYU professor Renata Forste in the Journal of Pediatrics, improvements in sensitivity to emotional cues and time reading to children could yield 2-3 months' worth of brain development by age 4, as measured by math and reading readiness assessments.

"Because these are four-year-olds, a month or two represents a non-trivial chunk of time," Gibbs said. "And if a child is on the edge of needing special education, even a small boost across some eligibility line could shape a child's educational trajectory."

They utilized a national data set that followed 7,500 mothers and their children from birth to five years of age. The data set is rich with information on the home environment, including how early and how often parents read to their kids. Additionally, each of the mothers in the study also participated in video-taped activities with their children. As the child tried to complete a challenging task, the mother's supportiveness and sensitivity to their child's emotional cues were measured.

The scholars note that the most at-risk children are also the least likely to receive the optimal parenting in early childhood. Single moms in the labor force, for example, don't have the same luxuries when it comes to breastfeeding and quality time with the children. Parents with less education don't necessarily hear about research-based parenting practices, either.

"This is the luxury of the advantaged," Forste said in their statement. "It makes it harder to think about how we promote environments for disadvantaged homes. These things can be learned and they really matter. And being sensitive to kids and reading to kids doesn't have to be done just by the mother."