Can Breastfeeding Keep Mom’s Heart Healthy?

Breastfeeding and heart health: breast milk is deemed to be the “best” for baby, but what are the additional benefits for mothers and their long-term health?

Cardiovascular disease remains one of the leading causes of death among the world’s population, with about 20 million people dying worldwide each year. One of the major precursors which can increase a patient’s risk of developing cardiovascular disease is a diagnosis of type 2 diabetes mellitus. Often patients with type 2 are immediately considered to be at high cardiac risk. Hypertension is linked to an increased risk of cardiovascular disease. Women specifically are dying at an alarming rate, which has led to studies that have explored non-traditional methods of decreasing a woman’s chance of developing diabetes, hypertension, and, ultimately, cardiovascular disease. A recent systemic review and meta-analysis were conducted to determine if lactation can ultimately decrease a women’s risk of developing diabetes and hypertension. While similar studies have been conducted, the sample sizes of these studies were very small, causing a disparity in the outcomes.

The major objective of this study was to retroactively review large groups of pregnant patients and determine if their decisions to either breastfeed or not had any effect on their risk of being diagnosed later in life with diabetes or hypertension. The patient information has come from previously conducted studies. After all of the data was gathered, 22 studies were used for the review. From there, 16 studies were excluded leaving six final studies for the final studies outcomes. It should, however, be noted that the studies that were not included in the final meta-analysis still provided important support information for the investigators.  In the final six studies that were evaluated, diabetes or hypertension was reported as an outcome. The final four studies that were included in determining the association between breastfeeding and diabetes contained 206,204 study participants. The final five studies that were selected to determine the link between breastfeeding and hypertension included 255,271 participants.

The investigators observed that breastfeeding for longer than 12 months led to a relative risk reduction of 30% for diabetes; this was in comparison to those who breastfed for less than a year. The odds ratio was calculated to be 0.70 (95% Cim 0.62-0.78; P<0.01). For those breastfeeding for longer than 12 months, there was a 13% relative risk reduction for hypertension. This was again in comparison to patients who breastfed for less than 12 months. The calculated odds ratio for this pool was 0.87 (95% CI, 0.78-0.97; P= .01). All data were adjusted for established cardiovascular confounders. The length of time a woman chose to breastfeed was shown to have some significance. The major weakness of the study design was the fact that the meta-analyses can only show association, not causation. Further studies would need to be completed to determine if a causative relationship exists.

The conclusion of this meta-analysis supports that breastfeeding mothers are at decreased maternal risk of being diagnosed with hypertension and diabetes later in life. The length of time a mother chooses to breastfeed is also significant, as better outcomes were observed when breastfeeding continued past 12 months. Both hypertension and diabetes are comorbidities that can significantly increase a patient’s risk of developing cardiovascular disease, and therefore every effort should be made to mitigate a potential diagnosis. It is of the utmost importance to educate pregnant women on not only the benefits of breastfeeding but also on the lifestyle factors they can change, which will provide long-term benefit. Tobacco cessation, exercise, and a healthy weight loss approach in addition to breastfeeding should be encouraged in the ante-natal period to facilitate better cardiovascular outcomes in mothers. Breastfeeding is also considered to be a low-risk intervention with a good potential for a positive reward, so clinicians should make it a priority to educate patients so that the long-term implications of their lactation choice is understood.

Practice Pearls:

• Diabetes and hypertension are potentially preventable comorbidities that increase a woman’s risk of developing cardiovascular disease.
• Education should be provided on the benefits of breastfeeding as well as lifestyle modifications that can work together to keep women as heart-healthy as possible. 
• All pregnant women should be encouraged to breastfeed as long as their lifestyles allow them, to get the most long-term health benefit.

Rameez RM, Sadana D, Kaur S, et al. Association of Maternal Lactation With Diabetes and Hypertension: A Systematic Review and Meta-analysis. JAMA Network Open. 2019;2(10):e1913401.

Jordan Boyd, PharmD. Candidate of Florida Agricultural & Mechanical University School of Pharmacy

See more about breastfeeding and heart health & breastfeeding and diabetes.