Breastfeeding, even for just a few days, tied to lower BP in early childhood

Infants who are breastfed, even for just a few days, have lower blood pressure (BP) at 3 years compared with their counterparts who have never been breastfed, according to the CHILD* study.

“Risk factors for poor cardiovascular health (including high BP), [can be] tracked from childhood to adulthood, and are influenced by early life exposures,” said the researchers.

The large prospective cohort study involved 2,382 children (98 percent ever breastfed) with data available on early life feeding and BP at 3 years of age. Among those who were ever breastfed, 4.2 percent had only been breastfed briefly during their birth hospitalization, termed as “early limited breastfeeding”. [J Am Heart Assoc 2021;doi:10.1161/JAHA.120.019067]

At 3 years of age, children who were ever breastfed showed BP that was lower than those who were never breastfed (mean systolic/diastolic BP, 99/58 vs 103/60 mm Hg).

The benefit of breastfeeding on BP also extends to infants who had only early limited breastfeeding, whose BP average at 99/57 mm Hg at the age 3 years.

“This is the first study to evaluate the association of breastfeeding in the first days of life and BP in early childhood,” said lead author Dr Kozeta Miliku of McMaster University in Hamilton, Canada. “Infants who received even a relatively small amount of their mother’s early breast milk, also known as colostrum, had lower BP at 3 years of age, regardless of how long they were breastfed or when they received other complementary foods.”

“Our study suggests that for cardiovascular outcomes such as BP, even a brief period of breastfeeding is beneficial. This points to colostrum as a key factor in shaping developmental processes during the newborn period,” said principal investigator Dr Meghan Azad from the University of Manitoba in Winnipeg, Canada.

Colostrum is known to be enriched with nutrients such as growth factors, immunologic components, polyunsaturated fatty acids, and stem cells which are important for cardiovascular health. 

“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,” Azad continued. “The benefits of sustained and exclusive breastfeeding are well documented for numerous health conditions, including respiratory infections and diarrhoeal disease during infancy, and chronic conditions including asthma and obesity later in life.”

Moreover, the association between breastfeeding and lower BP at age 3 years remained even after adjusting for multiple variables including the children’s body mass index or maternal health, social, or lifestyle factors.

Nonetheless, no causal relationship should be drawn from these findings due to the observational nature of the study. Also, only a single BP measurement had been collected instead of taking the average of several measurements, which was one of the study limitations.

“Despite the observational nature of our findings, the [findings] emphasize the importance of early breastfeeding initiation, even if exclusive or sustained breastfeeding is not possible,” Azad and co-authors pointed out. “These early subclinical differences could have long-term health implications because BP is known to track throughout life.”

“These findings emphasize the need for immediate postpartum lactation support in clinical settings to facilitate provision of colostrum and breastfeeding initiation,” they added.

*CHILD: Canadian Healthy Infant Longitudinal Development