Occasional breastfeeding shown to improve cardiac and vascular health in babies, with long-lasting benefits

By James DuckerReviewed by Emily Henderson, B.Sc.Jul 19 2021

New research shows that 3-year-old toddlers had lower blood pressure when they were breastfed as babies in comparison to ones that weren’t.

Woman Breastfeeding. Image Credit: Kingspirit Image Room/Shutterstock.com

Exploring cardiovascular disease risk factors in early childhood

The development and onset of risk factors for medical conditions such as cardiovascular disease has remained elusive, but recent studies have begun to show that cardiovascular disease risk factors, including high blood pressure, can start in childhood.

In addition to the onset of risk factors, research has also demonstrated that parental behavior affects the likelihood of such risks, and has shown that breastfeeding is associated with lower cardiovascular disease risk even into adulthood. However, the quantity and duration of breastfeeding required to achieve these beneficial outcomes has remained unclear.

To address this knowledge gap, researchers from Canada explored the impacts of breastfeeding over time and have published new findings in the Journal of the American Heart Association, an open-access journal of the American Heart Association.

Using data from the ongoing Canadian CHILD Cohort Study, which encompasses over 3,000 children to follow their development in an attempt to understand the importance of early life experiences, researchers analyzed infant feeding information collected from hospital records and caregiver questionnaires for nearly 2,400 children.

Within the whole sample, 98% of children were breastfed to some extent, including 4% who received "early limited breastfeeding", which was defined as a few breastfeedings during the hospital stay. Moreover, only 2% of children in the study were not breastfed at all.

Further sub-categorizing the children, 78% were breastfed for six months or more and 62% were exclusively breastfed for at least three months without any formula, solid foods, or fluids since birth. Data on the mothers was also collected, with mothers who never breastfed being younger, more likely to smoke during pregnancy, and less likely to have a post-secondary degree, compared to the mothers who breastfed briefly or beyond their hospital stay.

Following the information gathering and once the child was 3 years old, it underwent a physiological test to measure blood pressure.

Lower blood pressure even in occasionally breastfed children, with sustained and lasting benefits

Regardless of body mass index and any maternal factors, at 3 years old, children who were not breastfed had significantly higher blood pressures compared to those who were breastfed for any duration. Ones who received only limited early breastfeeding while in the hospital also had lowered blood pressure measures compared to those who were never breastfed.

This was hypothesized to be associated with colostrum, which is known to be especially rich in growth factors, immunologic components, and stem cells extremely beneficial to newborns and only found in human breastmilk.

This is the first study to evaluate the association of breastfeeding in the first days of life and blood pressure in early childhood. Infants who received even a relatively small amount of their mother's early breast milk, also known as colostrum, had lower blood pressure at 3 years of age, regardless of how long they were breastfed or when they received other complementary foods."

Kozeta Miliku, M.D., Ph.D., Clinical Science Officer of the CHILD Cohort Study

Senior study author Meghan B. Azad, Ph.D., deputy director of the CHILD Cohort Study and associate professor of pediatrics and child health at the University of Manitoba, describes: "The benefits of sustained and exclusive breastfeeding are well documented for numerous health conditions, including respiratory infections and diarrheal disease during infancy, and chronic conditions including asthma and obesity later in life,".

"Our study suggests that for cardiovascular outcomes such as blood pressure, even a brief period of breastfeeding is beneficial. This points to colostrum as a key factor in shaping developmental processes during the newborn period. For many reasons, sustained breastfeeding should be strongly supported, and it is also important to understand that 'every drop counts’, especially in those critical first few days of life."

Key implications for cardiovascular development and links to maternal behavior

The findings of this study suggest that breastfeeding is an essential activity for newborns that cannot be replaced effectively with supplements or alternative nutrition and that the effects are long-lasting for each individual.

Doctors and public health policymakers should consider the importance of educating new mothers about breastfeeding and offering immediate postpartum lactation support.

Our study's results suggest the short-term savings from not providing in-hospital breastfeeding support and discharging moms too quickly could be greatly outweighed by the long-term costs from reduced cardiovascular health later in life."

Dr. Azad

The limitations of this study also require consideration as it represents an observational analysis, meaning that further research has to be conducted to explore the exact reasoning of the findings. Furthermore, only a single blood pressure measurement, which may limit the extent of the findings, and future studies may benefit from additional time points to establish a temporal pattern of changes.

Importantly, researchers noted the need for further investigation to examine the exact bioactive components of colostrum. This will provide key insights into understanding how it influences cardiovascular development and affects long-term associations with cardiovascular health.