Breastfeeding an infant has been linked to many health benefits throughout life, including a reduced risk of sudden infant death syndrome, developing childhood leukemia, and developing depression as an adult. Now, new research published in Pediatrics from Oxford University researchers suggests that breastfeeding may also be able to improve the heart structure and function of babies born prematurely.

In 2014, about one of every 10 infants in the United States was born preterm, defined as being born before 37 weeks of pregnancy. Because their bodies haven’t had enough time to develop inside the womb, preterm babies face an increased risk of several health conditions later in life, including mental illness, severe cognitive deficits, and heart problems. Specifically, the study’s researchers noted that the hearts of premature babies usually grow to have smaller chambers and thicker walls, and therefore, reduced function.

These heart changes are believed to occur within the first few months after birth, so the researchers wanted to explore whether the way babies’ diets during this time period could alter how their hearts develop. For their study, they examined data on 102 adults in their early- to mid-20s who took part in an earlier study on the effects of different feeding regimens in preterm infants. This earlier study had followed them since birth, and contained detailed information regarding the long-term effects of diet on the heart’s development. The researchers also recruited 102 people who had not been born prematurely to serve as controls. All of them had their heart development and function assessed with magnetic resonance imaging.

The findings showed that while adults who were born early had reduced heart volume and function compared to those born at full term, the reduction wasn’t as drastic in those who were exclusively fed breast milk compared to those fed formula milk. Among preemies who were fed a combination of breastmilk and formula, researchers found that those who were fed the most breast milk had better heart structure and function as adults.

“Even the best baby formula lacks some of the growth factors, enzymes, and antibodies that breastmilk provides to developing babies,” lead study author Dr. Adam Lewandowski said in a statement. “These results show that even in people whose premature birth has inevitably affected their development, breastfeeding may be able to improve heart development.”

Though the researchers said this was the first study to provide evidence that breastfeeding promotes healthy heart development, it isn’t the first to uncover a link between breast milk consumption and heart health. A study published in 2014 found that breastfeeding can protect children from chronic inflammation, which plays a role in the development of heart disease and metabolic problems later in life. And in addition to better heart function, past research has also found that children who are breastfed are less likely to develop fatty liver disease in their teens.

Based on the findings, the researchers said the study supports the “promotion of human milk for the care of preterm infants to reduce long-term cardiovascular risk.”

Source: Lewandowski A, Lamata P, Francis J, et al. Breast Milk Consumption in Preterm Neonates and Cardiac Shape in Adulthood. Pediatrics . 2016.