Why Does Breastfeeding Reduce Breast Cancer Risk?

Breastfeeding can come with challenges, but it can also provide many benefits for both your baby and you as a woman. It can help your child fight off illnesses, help you bond with your baby, and recent studies have shown that breastfeeding can even reduce the mother’s risk of developing breast cancer later in life.

After skin cancer, breast cancer is the most common cancer among women in the United States. Recent research has shown that among other health benefits, women who breastfeed may also be lowering their risk of developing  post-menopausal breast cancer. This is mainly due to overall less lifetime exposure to the estrogen hormone.

Summary of today’s article:

How Does Breastfeeding Reduce The Risk Of Breast Cancer?

Many women know that breastfeeding can provide many benefits for newborns and infants. Breast milk contains all of the nutrition a newborn baby needs, including antibodies and vitamins that can help them fight off viruses and bacteria.

It has also been shown to lower their risk for Sudden Infant Death Syndrome (SIDS), while also lowering their risk of developing asthma and allergies. Studies have shown that breastfeeding can also help your baby maintain a healthy weight and it is thought that it can possibly lower their risk of developing diabetes and obesity as an adult.

For the mother, we know that breastfeeding can help you bond with your child, lower the risk of osteoporosis, and help lose pregnancy weight. Recent studies have shown there is an even more important benefit.

Breastfeeding can reduce your risk of developing breast cancer later in life. 

It is recommended to exclusively breastfeed your child for the first six months of their life and to continue until they are 2-years-old or even longer. Once a baby reaches six months of age, they are typically introduced to solid foods.

As they get older and continue to explore new foods, breastfeeding can and should still continue even after introducing other foods and drinks so they can still receive the optimal nutrition that breast milk provides.

This time spent breastfeeding can provide health benefits for the mother as well. Recent studies have shown that for every six months a woman breastfeeds, her risk of developing breast cancer decreases by 2% compared to women who have not breastfed their children.

Lactation Delays

After giving birth, many women who are breastfeeding do not start menstruating again immediately. This is due to hormonal changes that delay menstruation.

These changes include less exposure to hormones such as estrogen, which have been linked to breast cancer. Essentially, women who breastfeed are exposed to an overall lower amount of estrogen in their lifetime than women who do not breastfeed, thus decreasing their risk of developing breast cancer.

The amount of time a woman breastfeeds, both an individual child consecutively and multiple children over time, will determine how much her risk is lowered. The longer amount of time spent breastfeeding, the bigger a decrease in risk.

Breast Sheds Tissue

Pregnancy and breastfeeding both fundamentally change the structure of a woman’s breast. Even after a baby has been weaned, these changes are lasting and can continue to provide protection from pre-cancerous cells.

This is typically more common in women who have breastfed multiple children. During pregnancy and after lactation, the breast sheds tissue.

In doing so, it may be shedding cells with damaged DNA that could have otherwise led to the formation of cancer. This is another reason that breastfeeding can help reduce a woman’s risk of getting breast cancer. 

Gene Changes in Breast Cells

After a woman has stopped breastfeeding, there can also be changes in how genes are presented in her breast cells. These changes can stop the growth of possible pre-cancerous cells, protecting the mother.

Without breastfeeding, these changes may not have otherwise presented themselves, so it has been shown that these changes can help lower a woman’s risk of developing breast cancer.

How Long Do You Need to Breastfeed to See a Risk Reduction?

According to the American Institute for Cancer Research and the World Health Organization, it is recommended that a woman breastfeed for at least six months to receive the health benefit of lowering her risk of developing breast cancer. It has been proven that your risk begins to significantly lower at six months.

Any additional months spent breastfeeding would contribute to an even lowered risk. Furthermore, for every 12 months a woman breastfeeds, her risk is decreased by 4.3 percent. 

After six months of exclusively nursing, most infants begin eating solids. As new foods are introduced into your baby’s diet, you can and should still continue to breastfeed, thus further lowering your risk and continuing to provide your baby necessary nutrients.

Breastfeeding for longer than six months is beneficial for your child

Breastfeeding for longer than six months is beneficial for your child and also provides more protection to you as the mother against breast and ovarian cancers. 

For every six months of breastfeeding, a woman’s risk of breast cancer is lowered by 2%, but these months do not necessarily need to be consecutive. So, a woman who breastfeeds more than one child at separate times in her life, will benefit from the reduced risk of breast cancer based on the combined total number of months she breastfed her children.


Breastfeeding can reduce the risk of developing post-menopausal breast cancer. Research has shown that African American women do not receive the same benefits of decreasing their risk of breast cancer.

This is because white women more commonly get breast cancer post-menopause while Black women are more likely to experience premenopausal breast cancer. Since breastfeeding is not known to protect against premenopausal cancer, this would not help decrease the risk.

Does Breastfeeding Reduce The Risk Of Other Cancers Or Illnesses?

Breastfeeding can also reduce the risk of other cancers and illnesses, including ovarian cancer. It has been shown that women who nurse their child for over one year can see a significant decrease in their risk by 63% compared to women who breastfeed for less than seven months.

For those women who breastfeed more than one child for over 31 months combined, their risk decreases by 91% compared to those who nurse for 10 months.

Does Breastfeeding Help Reduce The Risk Of Cancer In The Child?

There is no link of breastfed children having a lowered risk of developing breast cancer later in life. However, studies have shown that babies who were breastfed for longer than six months do have a lower risk of developing certain childhood cancers including acute lymphoblastic leukemia, Hodgkin lymphoma and non-Hodgkin lymphoma. 

Other Risk Factors

Not including skin cancer, breast cancer is the most common cancer among women in the United States. Men can also develop breast cancer, but the risk is much higher for women. 

Like many illnesses and diseases, those with underlying health issues are at higher risk for developing breast cancer. Breastfeeding provides the benefit of lowering a woman’s risk of developing breast cancer later in life, but there are other factors that should be considered as well to maintain overall health.

After menopause, being overweight can lead to an increased risk of breast cancer. On the contrary, prior to menopause, body fat may help lower the risk of breast cancer.

It has been shown that one third of breast cancers in the United States could be prevented by exercising, eliminating alcohol consumption, and maintaining a healthy weight. Alcohol consumption can lead to an increased risk for breast cancer in both pre- and post-menopausal women.

Physical activity can reduce the risk in both as well. 

Breastfeeding Support

Many mothers are familiar with all of the benefits breastfeeding can provide to them and their baby and hope to breastfeed for months or even years. Unfortunately, breastfeeding is not always easy.

If you are having trouble, please reach out to a lactation consultant or breastfeeding specialist for help. Typically, your baby’s pediatrician or the hospital where you delivered, or plan to deliver, will have available resources.

There are also breastfeeding classes and support groups available where you can learn more from other mothers and receive assistance from specialists if needed. Breastfeeding can be wonderful for many reasons.

If you are struggling and want help, please do reach out to healthcare providers, friends, and family. Breastfeeding provides so many health benefits for both your baby and you as a mother, so it is well worth it to seek assistance if it is difficult.


Breastfeeding does not come without its challenges, but if you are able to successfully nurse your baby, the benefits are well worth the effort for both you and your child. Aside from providing ideal nutrition, breastfeeding can provide a number of health benefits for your child, including protection against certain illnesses.

Fortunately, breastfeeding can also provide unexpected health benefits for you as a woman, including reducing your risk of developing breast cancer later in life. Of course, breastfeeding alone will not prevent you from getting breast cancer, but if you are able to breastfeed, it would be a wonderful perk to reduce your risk and possibly contribute to maintaining good health post-menopause.