Breastfeeding’s Impact on Blood Pressure

Previous research shows women who breastfeed are more likely to have children with low blood pressure. However, a new study suggests breastfeeding’s effect on blood pressure may not be as significant as previously thought.

Researchers from London reviewed 24 studies to determine whether children of mothers who breastfeed are more likely to have lower blood pressure at different ages throughout childhood than children of mothers who do not breastfeed.

Results of the study show systolic blood pressure was slightly lower in breastfed children than in bottle-fed children. However, researchers found no significant difference in diastolic blood pressure between breastfed and bottle-fed groups. In addition, they found no specific trend among the different age groups studied.

Researchers also say most studies that show a strong correlation between breastfeeding and low blood pressure are small, which raises the possibility of publication bias. Authors of the study write, “Our systematic review found that publication bias may partly explain the lower mean systolic blood pressure observed in participants that had been breastfed in infancy, with large studies showing little difference.” Researchers add, even if publication bias did occur, the overall difference in systolic blood pressure was only 1.1 millimeters of mercury, which they say is fairly modest.

However, researchers still recommend that mothers breastfeed their infants because of other long-term benefits such as improved neural and psychological development, potential protection against obesity, and possible allergy immunity. Authors of the study conclude, “Our analysis suggests that any effect of breastfeeding on blood pressure is modest and of limited clinical or public health importance. However, blood pressure is not the only relevant outcome; the case for breastfeeding rests on a combination of short- and long-term benefits.”

SOURCE: British Medical Journal, 2003;327:1189-1192