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Are Your Gut Bacteria Putting You At Risk For Breast Cancer?

As I mentioned on Instagram the other day, I came across some really interesting research while working on case study this week. With Breast Cancer Awareness Month fast approaching I figured what better time to look a little bit into the link between the development of breast cancer and issues in the gut bacteria. As many of you know already, the gut microbiome is a topic of great interest to me and I discuss it often, but lets take a little look into how dysbiosis can affect something as seemingly unrelated as breast cancer.

As a quick refresher, the gut microbiome refers to the environment inhabited by the roughly 10-100 trillion microbial cells in our intestines, which generally form a beneficial, symbiotic relationship with us [1]. To be clear, as this is a relatively unfathomable number, the bacteria in your gut outnumber the “you” cells 10 to 1! [2] Now, we have already examined a little bit about how your gut bacteria, or microflora, can play a role in your management of stress, quality of sleep and general health in Part I and Part II of my series on the “3 S’s,” but what about cancer.

Well, it is already widely known and accepted the link between microbes, viruses and cancer. Helicobacter pylori (H. pylori) plays a role in the development of stomach cancer [2, 3, 4], while a number of strains are related to incidences of colorectal cancer [5, 6]. Moreover, the causal link between human papilloma virus (HPV) and cervical cancer has led for to the call for widespread preemptive vaccination [7].

So, what does that mean for breast cancer?

There are a number of potential mechanisms by which the gut dysbiosis can play a role in its development. Inflammation can result in changes in the microbiota [8], and increased intestinal permeability, which may play a role in the progression of breast cancer [9]. These bacteria can then release endotoxins, such as lipopolysaccharide (LPS), which can induce further inflammation, creating a vicious cycle, as well as in increasing metastasis [10].

Now, that is a major issue for the development of most cancers, but more specifically to breast cancer is with respect to the role of the gut bacteria in recycling steroid hormones, such as estrogen [11, 12]. During gut dysbiosis, estrogen is not properly metabolized leading to decreased 2-hydroxyestrone (2-OH) and increased 16α-hydroxyestrone (16-OH) [13]. A low 2/16 OH estrone (estrogen metabolite) urine ratio is indicative of breast cancer risk [14, 15].

Other mechanisms include bacterial-mediated changes to the immune response, including an increase in the release of neutrophils and in the destruction of lymphocytes [16, 17]. This is a problem as neutrophils can inhibit the immune response, while lymphocytes are immune cells that can initiate a potent anti-tumor response [18]. So, in short, the alteration of this ratio is associated with a decreased ability to fight off tumor progression and results in subsequent negative outcomes for breast cancer patients.

If that weren't enough, chemotherapy treatments can induce gut dysbiosis [19] and increase the risk of infection [20]. This in turn usually results in he administration of antibiotics, which also can have deleterious effects on the microbiome [21].

So, as a quick recap, the most common therapy alters the gut bacteria, which release toxins that further impair the immune response, necessitating antibiotics, which continue the cycle. General inflammation can also result in these changes, leading to further inflammation and changes in estrogen metabolism. Unfortunately, as is often the case in disease, it is a self-fulfilling prophecy.

But does this have to be your future?

Now, to be clear, breast cancer, and all other cancers for that matter, is a multifactorial disease and the gut bacteria are not the only factor in play. However, the research is continually emerging showing the interplay between gut dysbiosis and the development and progression of breast cancer.

Just as Hippocrates stated thousands of years ago, “disease begins in the gut,” and “let food be thy medicine and medicine be thy food.” Taking that advice to heart, it would be prudent to take measures to ensure the proper maintenance of both your intestinal wall integrity and in the health and diversity of your gut microflora.

Probiotics and digestive enzymes will assist with improving the status of the gut and in ensuring that nutrients are properly absorbed, but have also shown efficacy in improving cancer prognosis [22]. Personally, I have seen a lot of success with MegaSporeBiotic with respect to managing gut dysbiosis and it is without a doubt the top one I would recommend.

Next up would be the “Triple Threat” shakes and pudding recipes from Calton Nutrition. Whey protein, particularly when combined with gelatin, can reduce intestinal permeability, or “leaky gut” [23]. Moreover, whey protein has been found to possess anti-tumor properties [24, 25]. The medium chain-triglycerides (MCTs) in SKINNYFat provide an easily digestible energy source, despite malabsorption issues [26]. Whereas Nutreince provides a quality multivitamin that can help meet micronutrient sufficiency, as well assist in repairing the intestinal lining [27, 28].

Other potentially beneficial supplements include curcumin and milk thistle, which both exhibit anti-inflammatory and anti-tumor properties [29, 30]. Grapefruit seed extract is a compound with antimicrobial effects [31], which I have found very beneficial in correcting gut dysbiosis. Finally, deglycyrrhizinated licorice (DGL) has shown benefit in maintaining mucosal wall integrity [32], which is another barrier to prevent leaky gut.

Now once again, you should always discuss any nutrition and lifestyle changes with your physician or healthcare practitioner before embarking on them. But if you work on healing your gut, there are potentially some amazing benefits to be had towards living your optimal life!


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