Heart to Heart: Breastfeeding and Cardiovascular Health

by Jordan Berns

The impact of breast milk on infants is well-documented: it can help them build stronger immune systems while reducing their chances of having allergies, asthma, ear infections, diarrhea, and more. However, it’s not just baby who gets a health boost, it’s mom, too! Recent studies suggest that breastfeeding is linked to improved cardiovascular health in lactating mothers.

Cardiovascular disease, with coronary artery disease in particular, is the number one cause of death worldwide. According to the CDC, every 36 seconds someone in the United States dies from a cardiovascular related condition. Cardiovascular disease (CVD) occurs when there is buildup of plaque in the arteries that slow or halt blood flow. Cardiovascular-related deaths can also result from a bit of plaque breaking off, forming a blood clot that blocks blood’s normal path. Traditional risk factors for cardiovascular disease are high cholesterol, high blood pressure (hypertension), diabetes, smoking, a stationary lifestyle, a poor diet, and obesity.

Badly needed: the reason behind increased cholesterol in pregnancy.

During pregnancy, women are more likely to develop fatty plaque in their arteries, higher levels of total cholesterol (LDL cholesterol combined with HDL cholesterol), and very-low-density lipoprotein cholesterol (VLDL). Lipoprotein cholesterol (LDL) is what forms plaque. However, this is normal and usually a good thing! This increased amount of cholesterol production helps with fetal development and prepares a woman’s body for the breastfeeding process.

There is a revolutionary new hypothesis coming out of laboratories and medical offices: Breastfeeding seems to serve as a type of reset for the body’s metabolic changes that occur during pregnancy. Many now believe that breastfeeding helps remove excess cholesterol from the body. Additionally, the process of breastfeeding breaks down high-density lipoproteins (HDL) which induces a speedy drop triglycerides levels (fat that your body stores but doesn’t convert into energy).

Researchers all around the world are coming to a similar conclusion on breastfeeding and a healthy heart. A study from 2010 reported that women who breastfed for more than three months (after all mitigating factors were adjusted) had decreased odds for coronary and aortic calcification. A 2017 study published in the Journal of the American Heart Association examined 300,000 Chinese breastfeeding mothers; they were ultimately found to have exceptionally good cardiovascular health, but scientists are unable to explain why. These lactating women saw an approximate 20% reduction of cardiovascular issues as they aged, and every six months spent breastfeeding led to an additional 3 to 4% drop in the risk of having cardiovascular disease. A 2019 study on the relationship between breastfeeding and maternal cardiovascular disease yielded similar data. Australian mothers who breastfed their children for at least a year had a smaller chance of being hospitalized for cardiovascular disease (15% less) than other women their age who had not. Also, these women experienced 40% fewer deaths from complications of cardiovascular disease. However, as this latter experiment largely relied on self-reporting, the numbers cannot truly be confirmed.

One of the biggest risk factors for cardiovascular disease is hypertension (high blood pressure). The American Heart Association stated that the ideal blood pressure is below 120/80 mmHg (millimeters of mercury). High blood pressure during pregnancy is called gestational hypertension. Gestational hypertension is diagnosed when a pregnant woman’s blood pressure goes up to or exceeds 140/90 mmHg after an otherwise healthy first 20 weeks. This condition can be very dangerous and needs to be treated immediately. Coincidentally, after giving birth, most women experience lower levels of blood pressure. Each pregnancy a woman goes through results in a decreased chance of having hypertension.

Many scientists now believe that there’s a trend between the amount of time a woman spends breastfeeding and her having lower blood pressure. A 2011 study from the University of North Carolina, Chapel Hill published that mothers who breastfed for more than one year postpartum had healthier blood pressure levels than those who didn’t breastfeed or who breastfed for a shorter amount of time. However, these results all equalized after 11.5 years, although the preliminary screenings and follow-ups in this experiment were deemed by many to be substandard. Yet, these findings appear to be confirmed by an earlier 2005 study of breastfeeding Korean women who were found to have lower blood pressures than those who did not nurse.

Extra time spent breastfeeding could mean extra protection from cardiovascular disease.

Additionally, there is a high correlation between obesity, type 2 diabetes, and complications from cardiovascular disease. A 2007 study published by the Agency for Healthcare Research and Quality (AHRQ) revealed that the act of breastfeeding has a significant, positive impact on mothers’ health. In a study of childbearing women, it was discovered that every year a mother spends breastfeeding, there was a 4% to 12% reduction in mothers who contract type 2 diabetes. While the research has yet to be sufficiently peer reviewed, a 2017 joint experiment by scientists from Atlanta, Georgia and Pittsburgh, Pennsylvania, made the claim that the extra weight gained during pregnancy is meant to be used as energy for lactation. They conjectured that breastfeeding almost exclusively for 5-6 months postpartum is linked to healthy weight loss. A 2012 study from Norway consisting of over 21,000 mothers (who were less than 50 years of age), established that the women who had not breastfed were 3.37 times more likely to be obese than those who had sustained periods of nursing. However, the odds equalized after mothers turned 50 years old.

Although the research appears to suggest that breastfeeding mothers are healthier than their non-breastfeeding counterparts, scientists are still puzzled as to why. Some believe that breastfeeding women may make more health conscious decisions because their nutritional intake directly affects their babies’ growth. One thing is for certain: it’s that this will surely be a fascinating subject to learn more about in the years to come. In the meantime, the best ways to prevent cardiovascular disease are avoiding tobacco products; reducing intake of alcohol, processed carbohydrates, sugar, salt, saturated and trans-fat; maintaining a healthy weight; enjoying restful sleep; exercising 30 to 60 minutes a day; and seeing your doctor regularly for checkups.