Does Breastfeeding Strengthen the Heart?

It may sound incongruous that pregnancy increases the risk of myocardial infarction by more than three times,whereas breastfeeding cancels out this risk. However, a study found that breastfeeding, especially for longer durations, helps reduce the risk for heart attack.2

The research presented at American College of Cardiology’s 67th Annual Scientific Session looked at long-term health benefits of breastfeeding. It revealed that women with normal blood pressure during pregnancy who breastfed for at least 6 months had a significantly higher good cholesterol levels, lower levels of triglycerides and healthier carotid arteries thickness, as compared to women who had never breastfed. Moreover, such women had better cardiovascular health years and even decades after their infants have grown up.3

However, no evidence of cardiovascular benefit from breastfeeding was found among women who had hypertension during pregnancy. This may be attributed to a small number of women participants with high blood pressure during pregnancy. So, future studies that involve more participants are needed.

While pregnancy puts a strain on the cardiovascular system, nursing helps to restore the mother’s heart health to its pre-pregnancy state. Although, it is not clear how exactly breastfeeding strengthens the heart, the researchers think that it is a nature’s way of lessening the physical cost of having a child.

The precise mechanism of the study findings is yet to be found. However, scientists hypothesize that the lower risk of myocardial infarction and stroke can be due to metabolism reset after pregnancy.

During pregnancy a woman’s body stores more fat to provide energy for both the fetus’s growth and breastfeeding after the child is born. That’s why the woman’s belly waist circumference increases, regardless of how much she weighed before getting pregnant. The abdominal fat, in its turn, increases the risk for metabolic syndrome – a well-known constellation of risk factors for heart disease. However, this adverse effect of pregnancy can be reduced by breastfeeding as it helps to eliminate that stored fat faster. On the contrary, women who don’t breastfeed have metabolic reserves that they don’t need, which contributes to more weight gain and raises the risk for atherosclerosis.

Furthermore, breastfeeding women tend to adopt healthy behaviors, such as exercising, eating wise and not smoking, which aid cardiovascular health when compared to non-breastfeeding women.

Another hypothesis is that breastfeeding increases the levels of oxytocin hormone, which can modify the heart rate and blood pressure both through its effects on the central nervous system and other organs, such as heart, kidney and blood vessels.

Although further researches are needed to give more definite data, the body of evidence that points to a very good effect on heart and overall health is growing. So, doctors recommend breastfeeding for at least a year not only for the baby’s health, but for the woman’s own health as well.

However, women shouldn’t be made to feel guilty if they don’t breastfeed because there can be reasons behind it, such as job or health issues that prevent them from making it to a full year.

At the same time, neither study presupposes that women who choose not to breastfeed or can’t make it will necessarily develop cardiovascular issues.


  1. Honigberg MC, Scott NS. “Pregnancy-Associated Myocardial Infarction”. Current Treatment Options in Cardiovascular Medicine. 20(7):58. June 19, 2018.
  2. Stuebe AM, Michels KB, “Duration of lactation and incidence of myocardial infarction in middle to late adulthood”. American Journal of Obstetrics and Gynecology. 200(2):138.e1-8. February 2009.
  3. “Breastfeeding May Have Long-Term Heart Health Benefits for Some Moms”. American College of Cardiology. February 28, 2018.