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The Breast Microbiome

Most of us are all too familiar with how important balancing gut bacteria. But, did you also know that your “microbiome” exists in more places than just your gut?






One important microbiome exists in mammary tissue. In recent years, additional studies have played a vital role in discovering the link between both beneficial and pathogenic bacterium and Breast Cancer.


One study was conducted in 2016 by the Mayo Clinic and published in journal Scientific Reports. The researchers found that breast tissue may contain bacterial DNA even when there was no sign of infection in the area. They also saw different types of bacteria in women with Breast Cancer and women without Breast Cancer.


Another related pivotal study has helped to narrow down the specific kinds of bacterial strains that can affect Breast Cancer risk. This investigation was led by Dr. Gregor Reid of the Western University in Ontario, Canada in 2016. Dr. Reid and his team discovered that “microbes in the breast, even in low amounts, may be playing a role in breast cancer—increasing the risk in some cases and decreasing the risk in other cases.”


The study, which was published in the medical journal Applied and Environmental Microbiology, found that women who had the highest levels of Enterobacteriaceae, Staphylococcus and pathogenic strains of Bacillus also had the highest cancer risk.


All of these bacteria are “gram-negative” and are associated with severe disease conditions in general, as well as higher Breast Cancer risk when found in high amounts in breast tissue. Enterobacteriaceae, for example, is associated with respiratory infection. Staphylococcus, or “staph,” is associated with endocardium (a potentially serious heart condition), Toxic Shock Syndrome, and infection deep within the bones and joints. Finally, Bacillus often forms on spoiled food and can be especially prevalent in commercial dairy products. It can produce many kinds of toxins, including B. anthracis, or Anthrax.


On the other hand, high levels of beneficial bacteria such as Lactococcus and certain strains of  Streptococcus were present in the breast tissue of women whose Breast Cancer risk was low. Lactococcus is a lactic acid bacteria that is often found in breast milk. Many investigations,  including a 2019 study conducted by the National Research Council in Valencia, Spain, support the fact that breast feeding inoculates newborn babies with healthy probiotic bacterium which can help their gut health, and their health in general, as they grow into adulthood.

In addition, Streptococcus has been found to have anti-carcinogenic properties and is considered a powerful antioxidant substance. It has the ability to help prevent DNA damage as a result of oxidation.


What Can You Do To Improve Your Breast Area Microbiome?


1. Eat a healing diet that does not promote the growth of bad bacteria.

This means swapping out all of those foods which are sugar-heavy as well as simple carbs like pasta and pastries for green leafy veggies and low sugar fruits like green apples and including pure sources of healthy fats and proteins.


2. Manage stress.

This is critical for your healing journey overall and for balancing your breast area microbiota too. That “fight or flight response” is great when you are in danger but leaving it “turned on” 24/7 increases inflammation and creates an environment where pathogenic bacteria can grow.


3. Probiotics

You can eat fermented foods to support the good bacteria and find a good probiotic to take as part of your daily regimen.

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