Breastmilk and the developing infant brain

In a previous post, we discussed how the composition of human breastmilk protects infant health and aids in the early development of the gut and immune system. We also talked about how some of those beneficial properties can be isolated to specific milk proteins that can now be produced affordably, in high yield, for clinical studies investigating their benefits in older adults.

Of course it goes without saying that breastmilk also supports the development of every organ system as a baby grows from helpless neonate to walking, talking toddler. Breastmilk efficiently combines the macronutrients, vitamins, minerals, and non-nutrient factors into a readily bioavailable form that supplies everything needed for explosive gains in weight, bone and muscle mass, neural development, and a host of other interrelated processes that take place in the first year of life. Now, in a study from the University of Edinburgh, researchers have shown that breastmilk confers important benefits to brain development in premature infants.

Breastmilk supports development of greater neural connectivity in the weeks after pre-term birth

Part of a longitudinal study designed to investigate the effects of preterm birth on brain structure and outcome, this sub-study aimed to distinguish between how genetic, comorbid, and nutritional factors contribute to the neurocognitive impairments associated with pre-term birth, in 47 infants admitted to the neonatal care unit after being born at less than 33 gestational weeks.1

Brain MRI data collected when the infants reached term-equivalent age suggested that breastmilk was associated with dose-dependent improvements in white matter microstructure, including greater fractional anisotropy-weighted neural connectivity and increased FA within the white matter. The beneficial effects were distributed throughout the white matter, including the corpus callosum, cingulum cingulate gyri, centrum semiovale, corticospinal tracts, arcuate fasciculi and posterior limbs of the internal capsule. Infants exclusively fed breastmilk for more than 90% of their time in the hospital showed greater sub-cortical connectivity than those receiving  breastmilk exclusively for at least 75% of the time. Infants fed breastmilk exclusively for less than 75% of their in-patient stay showed the least favorable results.

The benefits of breastmilk components remain to be fully explored

The authors concluded that pre-term infants fed breastmilk in the weeks immediately after birth benefit from improved structural neural connectivity and white-matter development. While the specific mechanisms behind these effects were not explored, the results are consistent with other published studies that have found that breastfeeding is associated with better neurodevelopmental outcomes in pre-term infants. It will be of future interest to understand how the individual components of human breast milk affect the process of neural development, either directly or through their influence on the gut biome and the gut-brain axis. This information may lead to greater insight into whether breastmilk components may be protective or even therapeutic for pathological processes in the brain associated with disease and aging.


  1. Blesa M, Sullivan G, Anblagan D et al. Early breast milk exposure modifies brain connectivity in preterm infants. Neuroimage. 2018;184:431-439.