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Breastfeeding Boosts the Brain Development of a Baby

Just 3 months of breastfeeding boosts brain growth by 20 to 30 percent.

Key points

  • Research shows that breastfeeding can increase the growth of white matter in a baby's brain by 20-30%.
  • Exclusively breastfed babies show more brain growth before age 2 than formula-fed babies or those fed both ways, according to research.
  • One study shows that breastfed children older than age 2 show increased language performance, visual perception, and motor control performance.

There is growing evidence that breastfeeding improves the brain development of infants. Researchers at Brown University have discovered that breastfeeding alone produces the best results for boosting a baby’s brain growth. Breastfeeding can increase a baby’s brain growth by 20 to 30 percent.

The researchers found that a combination of breastfeeding and formula produced better development than formula alone. The study, titled “Breastfeeding and Early White Matter Development: A Cross-Sectional Study,” was published on June 6, 2013, in the journal NeuroImage.

Previous behavioral studies have associated breastfeeding with better cognitive outcomes in older adolescents and adults. A 2011 study from Oxford University and the Institute for Social and Economic Research, Essex University, found that breastfeeding improved cognitive development and allowed children to do better in school. However, this is the first brain imaging study that looked for differences associated with breastfeeding in the brains of very young and healthy children, said Sean Deoni, assistant professor of engineering at Brown and the study's lead author.

Breastfeeding Stimulates White Matter Brain Growth

"We're finding the difference [in white matter growth] is on the order of 20 to 30 percent, comparing the breastfed and the non-breastfed kids," said Deoni. "I think it's astounding that you could have that much difference so early."

The study used a very quiet and baby-friendly magnetic resonance imaging (MRI) to look at the brain growth in a sample of children under the age of 4 while they slept. Deoni and his team looked at 133 babies ranging in ages from 10 months to 4 years. All of the babies had normal gestation times and came from families with similar socioeconomic statuses.

Sean Deoni has developed a specialized MRI technique that looks at the microstructure of the brain's white matter, the tissue that contains long nerve fibers and helps different parts of the brain communicate with each other. Specifically, the technique looks for amounts of myelin, the fatty material that insulates nerve fibers and speeds up the electrical signals between neural networks within the brain.

The researchers split the babies into three groups: those whose mothers reported they exclusively breastfed for at least three months, those fed a combination of breastmilk and formula, and those fed formula alone. The researchers compared the older kids to the younger kids to establish growth trajectories in white matter for each group.

The researchers found that by age 2, babies who had been breastfed exclusively for at least three months had enhanced development in key parts of the brain compared to children who were fed formula exclusively or who were fed a combination of formula and breastmilk. The extra growth was most pronounced in parts of the brain associated with language, emotional function, and cognition, the research showed.

Duration of Breastfeeding Increases Brain Growth

The study also looked at the effects of the duration of breastfeeding. "We wanted to see how early these changes in brain development actually occur," Deoni said. "We show that they're there almost right off the bat." The researchers compared babies who were breastfed for more than a year with those breastfed less than a year, and found significantly enhanced brain growth in the babies who were breastfed longer—especially in areas of the brain dealing with motor function.

The study showed that the exclusively breastfed group had the fastest growth in myelinated white matter of the three groups, with the increase in white matter volume becoming substantial by age 2. The group fed both breastmilk and formula had more growth than the exclusively formula-fed group, but less than the breastmilk-only group.

Deoni and his team then backed up their imaging data with a set of basic cognitive tests on the older children. Those tests found increased language performance, visual perception, and motor control performance in the breastfed group.

Conclusion: Lifestyle Choices Impact Brain Development Throughout a Lifetime

There is growing evidence that the daily choices we make as parents and individuals impact brain health and cognitive development. The brain is plastic and continues to reshape throughout a lifetime. It is never too late to be proactive and make lifestyle choices that will bulk up the gray and white matter of all hemispheres of your brain.

Deoni concludes, “The findings add to a substantial body of research that finds positive associations between breastfeeding and children's brain health,” adding, “I think I would argue that combined with all the other evidence, it seems like breastfeeding is absolutely beneficial.”

If you’d like to learn more about the neuroscience of childhood development please check out my Psychology Today posts: "The Neuroscience of Calming a Baby," "Science Confirms Why 'Oh, the Places You’ll Go' Is Genius" and "Neuroscientists Discover Keys to Individual Personality."

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