What Breastfeeding Might Do for Baby's Brain

Breastfeeding longer tied to higher intelligence, education levels and income

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Breastfeeding may boost more than just bonding — it may also boost baby's brainpower based on how long you do it.

That's the takeaway from a new study. Also, educational attainment and income were tied to the duration of breastfeeding.

Lead study author Bernardo Lessa Horta, MD, noted in a press release that breastfeeding's effect on brain development was well-known, but how long these effects last was unclear.

“Our study provides the first evidence that prolonged breastfeeding not only increases intelligence until at least the age of 30 years but also has an impact both at an individual and societal level by improving educational attainment and earning ability," Dr. Horta said. "What is unique about this study is the fact that, in the population we studied, breastfeeding was not more common among highly educated, high-income women, but was evenly distributed by social class.”

Robert Kotas, MD, a board-certified pediatrician at Baylor Pediatric and Adolescent Associates in Murphy, TX, told dailyRx News that breast milk is the best source of nutrition for infants.

"Breast milk is high in long-chain polyunsaturated fatty acids, which are critical nutrients for brain development," Dr. Kotas said. "There are also enzymes, sugars, and probiotics in breast milk that act in concert with these fatty acids. How they interact with fatty acids is still unknown."

Researchers led by Dr. Horta, of the Federal University of Pelotas in Brazil, studied data on almost 3,500 infants to determine whether breastfeeding for longer periods affected intelligence, income and education.

Dr. Horta and colleagues used data from a study that started in 1982 and included data on breastfeeding patterns among Brazilian mothers. These researchers then followed up on the infants, who were then about 30 years old, and gave them IQ tests.

Also, Dr. Horta and team collected data from the adults about their educational achievements and income.

These researchers divided the study subjects into five groups based on the length of time they were breastfed as infants. Breastfeeding duration in the groups ranged from less than one moth to a year or more.

The longer a child was breastfed — up to one year — the greater the benefits, Dr. Horta and team found. All levels of breastfeeding were tied to increased adult intelligence, longer schooling and higher earnings as an adult.

Infants who were breastfed longer had even more significant gains.

For instance, infants breastfed for at least a year had average IQ scores a full 4 points above those who were breastfed for less than one month. Infants who were breastfed for at least a year had almost one more year of schooling and earned almost one-third more than those who were breastfed for one month.

Dr. Kotas said breast milk may bring more than just brain benefits.

"Other benefits of breastfeeding include less risk of sudden infant death syndrome (SIDS), meningitis, ear infections, respiratory diseases, and diarrhea," he said. "There is also protection against chronic diseases such as Type 1 diabetes mellitus, Crohn’s disease, obesity, and celiac disease."

This study was published in the March issue of the journal The Lancet Global Health.

The Wellcome Trust, International Development Research Center of Canada, CNPq, FAPERGS and the Brazilian Ministry of Health funded this research. Dr. Horta and team disclosed no conflicts of interest.

Review Date: 
March 16, 2015
Last Updated:
March 20, 2015