Breast milk is more than a meal. It contains components capable of impacting critical development in newborns.
New research from UC San Diego School of Medicine shows that a single sugar in breast milk supports gut development and prevents jaundice in babies. While the result is preliminary, the researchers hope the finding could lead to the development of a supplement that can improve infant health.
“We found this sugar can even affect breast milk development and also even the development of the jaundice,” said Xiaojing Yang, a staff research associate at UC San Diego School of Medicine.
The team was surprised by the finding, she said, because of how closely small intestine development and jaundice are connected.
Jaundice is a condition that affects up to 60% of newborns shortly after birth, according to the Centers for Disease Control and Prevention. Babies with jaundice temporarily develop yellow skin and eyes. It’s caused by a build up of a chemical called bilirubin in blood.
Most infants develop the ability to process bilirubin as they get older. However, if left untreated for a long enough period of time, jaundice can lead to brain damage.
To find out if breast milk sugar impacts the breakdown of bilirubin, UC San Diego School of Medicine examined the role it played in gut development in mice pups.
The small intestine can help clear bilirubin from infants' systems, Yang said. It produces an enzyme that removes the chemical.
The study focused on a sugar called 3’-sialyllactose (3’SL). The researchers investigated how the 3’SL influences gene expression and the production of the bilirubin-clearing enzyme found in the gut.
“We found that the 3’SL can help the intestine to build the ability to remove the bilirubin in the neonatal stage,” Yang said.
Yang and her team also found that removing the sugar from breast milk had adverse effects on the mice. The pups who were not on a 3’SL diet had more severe jaundice. They were also more likely to die and have a shorter, less functional intestine.
“We found some very important functional cells … they don't express very well if there's no sugar feeding,” Yang said.
Breast milk research is often centered around antibodies, or proteins that help fight off infections, and how they can help babies’ immune systems, Yang said. But this study highlights how other components in breast milk may impact crucial development in newborns in the future.
“Now we also know there are some chemicals in the breast milk (that) can help our babies,” Yang said. “It's more than just feeding your baby. It can really impact future development.”
Yang hopes that one day, the 3’SL sugar could lead to a supplement that can help parents support their baby’s development.
But because the study was only performed in mice, more research will be needed to achieve that goal. The next steps will be to see how this sugar impacts human cells.
