Could Your Gut Be Affecting Estrogen Balance? The Gut-Hormone Connection
If you deal with PMS, heavy or painful periods, breast tenderness, fibroids, or endometriosis, you've probably heard the term estrogen dominance. Most conversations about estrogen focus on the ovaries and hormone production. But there's another important player that doesn't always get mentioned: your gut.
From a naturopathic perspective, hormones are never just about one organ. They're about the whole system—how hormones are made, how they're broken down, and how they leave the body.
That last step is where your gut microbiome and an enzyme called beta-glucuronidase enter the story.
What Does Estrogen Dominance Mean?
Estrogen dominance doesn't necessarily mean that your estrogen level is extremely high on a lab test. The term is often used to describe a situation in which estrogen is high relative to progesterone.
Symptoms sometimes associated with this pattern can include changes in mood before your period, heavy or painful periods, breast tenderness, water retention, headaches, or cycle-related migraines. Conditions such as fibroids and endometriosis are also commonly discussed in the context of estrogen-related health.
If several of these symptoms sound familiar, it may be worth looking beyond hormone production alone and considering how your body is metabolizing and eliminating estrogen.
How Your Body Processes Estrogen
Here's how it's supposed to work.
When your body is finished using estrogen, the liver processes it through a pathway called glucuronidation. In simple terms, the liver attaches a glucuronic acid molecule to the hormone, helping make it inactive and water-soluble so it can be eliminated from the body.
The packaged estrogen is then released into bile, travels into the intestines, and is ultimately intended to leave the body through stool.
But this is where your gut bacteria become part of the conversation.
Certain gut bacteria produce an enzyme called beta-glucuronidase. This enzyme can remove the glucuronic acid tag from estrogen, allowing the hormone to become active again. The estrogen can then be reabsorbed through the intestinal wall and returned to circulation.
This process is known as enterohepatic recirculation, and it means that the gut microbiome can play a role in how much estrogen is eliminated versus recycled.
Meet the Estrobolome
Researchers have a name for the collection of gut bacterial genes involved in estrogen metabolism: the estrobolome.
The estrobolome is an area of growing research because scientists are working to better understand how differences in the gut microbiome may influence estrogen metabolism and hormone-related health.
In 2016, Kwa and colleagues proposed that individual differences in the estrobolome could influence the risk of certain estrogen-related conditions, including estrogen receptor-positive breast cancer. They also suggested that future microbiome-directed approaches, including prebiotics and probiotics, could potentially influence this pathway. Importantly, these were proposed mechanisms and areas for future investigation rather than established treatments. [1]
A 2017 review of the estrogen-gut microbiome axis similarly described the relationship between gut bacteria and estrogen metabolism and discussed potential connections with conditions including endometriosis, endometrial hyperplasia, PCOS, fertility, obesity, metabolic syndrome, cardiovascular health, and cognitive function. [2]
More recently, a 2023 review in Gut Microbes focused specifically on gut microbial beta-glucuronidase and its potential role in estrogen metabolism across a woman's lifespan. The authors described beta-glucuronidase as an important area of investigation and suggested that measuring or modifying its activity could eventually have clinical applications. [3]
The research is promising, but much of this area is still developing. We are continuing to learn how individual differences in gut bacteria influence estrogen metabolism and what interventions may meaningfully change that process.
What Can Affect the Gut-Estrogen Connection?
One of the key factors researchers continue to investigate is gut dysbiosis, or an imbalance in the gut microbiome.
Changes in microbial diversity and the presence of different bacterial species can influence beta-glucuronidase activity and, in turn, potentially affect estrogen metabolism. The relationship isn't necessarily as simple as “more beta-glucuronidase is bad,” either. Your body needs normal enzyme activity, and the research suggests that balance and the overall composition of the microbiome matter. [2,3]
From a naturopathic perspective, this is one reason we pay attention to the foundations of gut health, including nutrition, fiber intake, alcohol consumption, and environmental exposures.
Dietary fiber can support a diverse gut microbiome, while cruciferous vegetables such as broccoli and Brussels sprouts provide nutrients and plant compounds that are often incorporated into hormone-supportive nutrition strategies.
Adequate protein and key nutrients also support normal liver function and the body's natural detoxification processes.
Environmental exposure is another consideration. Some chemicals found in plastics, pesticides, and fragranced products can have estrogen-like activity and are commonly referred to as xenoestrogens. Reducing unnecessary exposure can be one practical way to decrease the overall estrogenic load your body encounters.
Simple changes might include storing food in glass rather than plastic when practical, choosing fragrance-free personal care products, and washing produce thoroughly.
Can You Test Beta-Glucuronidase?
If you're curious about what's happening in your gut, comprehensive stool testing can measure beta-glucuronidase levels.
Testing can sometimes provide another piece of the puzzle when evaluating digestive health and hormone metabolism. However, test results should be interpreted in the context of your symptoms, health history, diet, medications, and other relevant factors rather than viewed in isolation.
The goal isn't to completely eliminate beta-glucuronidase. Your body needs normal physiological processes to function properly. Instead, the goal is to support a healthy, balanced gut environment and the body's natural pathways for processing and eliminating hormones.
Supporting the Gut-Hormone Connection
Your hormones and your gut are not separate systems. The way your body produces, processes, recycles, and eliminates hormones involves multiple organs and pathways working together.
Understanding the estrobolome and the role of beta-glucuronidase gives us another lens through which to understand estrogen metabolism. While research is still evolving, supporting overall gut health through nourishing food, adequate fiber, balanced nutrition, and thoughtful lifestyle choices can be an important part of a whole-person approach to women's hormone health.
Rather than simply asking, “How can I lower my estrogen?”, it may be more helpful to ask, “How is my body processing and eliminating estrogen, and what might be influencing that process?”
Looking to Support Your Gut and Hormone Health?
Experiencing PMS, painful or heavy periods, digestive concerns, or other symptoms that make you wonder whether your gut and hormones may be connected?
Book a FREE 15-minute meet and greet to learn how personalized functional and integrative care may help support your gut health, hormone balance, digestion, and long-term women's health goals.
Author: Dr. Stephanie Hendershot, ND
References
Kwa M, Plottel CS, Blaser MJ, Adams S. The intestinal microbiome and estrogen receptor-positive female breast cancer. J Natl Cancer Inst. 2016;108(8). doi:10.1093/jnci/djw029.
Baker JM, Al-Nakkash L, Herbst-Kralovetz MM. Estrogen-gut microbiome axis: Physiological and clinical implications. Maturitas. 2017;103:45-53. doi:10.1016/j.maturitas.2017.06.025.
Hu S, Ding Q, Zhang W, Kang M, Ma J, Zhao L. Gut microbial beta-glucuronidase: a vital regulator in female estrogen metabolism. Gut Microbes. 2023;15(1):2236749. doi:10.1080/19490976.2023.2236749.
Disclaimer: This information is generalized and intended for educational purposes only. Due to potential individual contraindications, please see your primary care provider before implementing any strategies in these posts.
