This article has been medically reviewed by Dr. Charles Penick, MD
Microbiome and Hormone Health: Gut health has become a hot topic in the world of wellness due to its profound influence on an array of health markers. Today we explore the microbiome and its particular impact on female hormonal health and balance.
Microbiome and Hormone Health: What Is The Microbiome?
A microbiome is an environment that contains living bacteria. There are various types of microbiomes, including the human body biome as a whole, or individual ecosystems within the body like the skin biome, the mouth biome, and the gut biome.
Bacteria play a crucial role in generating our existence and health, for there are more bacterial cells in the human body than human cells. There are approximately 40 trillion bacterial cells to 30 trillion human cells. [1, 2] An optimally healthy gut should contain 20,000 – 30,000 different bacteria species. Most people living a modern “standard American” lifestyles includes under 1,000 species. 
The human gut microbiome facilitates a wide range of bodily functions, including digestion, absorption, and assimilation of nutrients, immune regulation, brain health, and hormonal production. [4-6] For this reason, having a microbially diverse gut is one of the most important aspects of maintaining whole-body health and longevity.
Microbiome and Hormone Health: The Microbiome Hormone Link
Hormones are signaling molecules that target organs to regulate physiology and behavior. The two main female hormones are estrogen and progesterone, which play a major role in metabolism and reproduction.  Too much or too little of any hormone can have a dramatic effect on the whole body.
Hormonal imbalances are prevalent in women; studies suggest that 80 percent of women suffer from hormonal imbalances. Symptoms of female hormone imbalances include: [8-12]
- Weight gain
- Dry skin
- Overly cold or overly hot
- Muscle aches or tenderness
- Still joints
- Low or no libido
- Thinning hair
The relationship between the gut microbiome and estrogen is deeply intertwined, with much cross-talk between the two.  The relationship impacts microbial diversity, estrogen metabolism and dominance, inflammation, and gut lining.
Microbiome and Hormone Health: Estrogen to Promote Microbial Diversity
Although estrogen is a significant player in reproductive health, it also plays a crucial role in various other functions. One such function is the promotion of growth and proliferation of good gut bacteria.  When the gut bacteria is imbalanced (known as gut dysbiosis), genes and pathways are activated that influence sugar and carbohydrate metabolism negatively. One route, known as the TLR4 pathway, is linked to insulin resistance, and an array of illnesses that can cascade as a result. 
Estrogen Metabolism and Dominance and Breast Cancer
Your gut microbiome plays a significant role in metabolism, which is important in keeping your hormones in balance. Female hormones fluctuate throughout the month, and estrogen is one of the hormones that can cause various problems when it is not metabolized well (known as estrogen dominance).
The gut biome breaks down estrogen by secreting an enzyme called β-glucuronidase. This enzyme breaks estrogen down into a free, biologically active form that can be taken up into the body’s tissues.  And so gut dysbiosis can impair the process of estrogen metabolism, resulting in excess free estrogen levels not being appropriately used in the body.
One of the most lethal links between disease and excess estrogen in the body is hormone-dependent cancers, especially breast cancer, ovarian cancer, and endometrial cancer in women. As well as increased risk of blood clots and stroke. 
Although estrogen dominance is considered a hormonal imbalance with health consequences, estrogen itself is not ‘bad’ and has many critical roles in the body when in balance. Estrogen helps manage weight (especially abdominal fat), and promote glucose tolerance when produced and metabolized properly.
Estrogen, Gut Lining, and Inflammation
When it is produced and metabolized correctly, estrogen helps reduce inflammation in the body and protect the integrity of the gut lining. It decreases the pathogenic populations of bacteria and the inflammation caused by lipopolysaccharide (or LPS).
LPS can interfere with gut lining and cross the body’s gut barrier, causing a highly inflammatory response. Breaking down the gut lining, LPS can also open up the flood gates for all sorts of other inflammatory causing invaders. Estrogen works to protect the integrity of the gut lining by eliminating LPS and has a preventative anti-inflammatory role. 
Maintaining the integrity of the gut lining is very important for overall health. This lining acts like a barrier between the outside world (pathogens, bacteria, viruses, and other inflammatory inducing agents) and your body. Gut permeability (leaky gut) is linked to a wide range of disease models known to science, including Crohn’s disease, celiac disease, type 1 diabetes, type 2 diabetes, rheumatoid arthritis, spondyloarthropathies, inflammatory bowel disease, irritable bowel syndrome, schizophrenia, and certain types of cancer. 
Estrogen also helps produce a more robust gut lining because it is needed to form the gut’s epithelial layer and maintain a healthy, elastic, and tight junctions.  It not only prevents breakdown from lipopolysaccharides but also helps strengthen the lining itself from unwanted molecules.
Microbiome and Hormone Health: Tops Ways To Improve Microbial Diversity in the Gut
Avoid Anti-Microbial Foods and Agents
Consuming good bacteria is only useful if you’re mindfully avoiding the types of foods and other agents that kill bacteria. The anti-bacterial movement that swept the nation in favor of killing harmful bacteria does not selectively kill the bad. By using harsh anti-bacterial agents (like soaps, hand sanitizers, and antibiotics), the good bacteria get bombed as well. 
Certain types of food and beverages target bacteria and make it very difficult for the good bacteria to survive. They include artificial sweeteners, vegetable oils, and other PUFAs, alcohol.
Increase Consumption of Live Fermented Foods
Fermented live foods contain live probiotics and enzymes that can help increase the microbial diversity of your gut.  Aiming to consume at least one serving of fermented foods a day is ideal, but one serving per meal is optimal. Fermented foods include:
- Yogurt (unpasteurized)
- Kefir (unpasteurized)
- Beetroot kvass
Increase Consumption of Prebiotic Foods
Prebiotic foods are rich in dietary fibers and sugars that feed the good bacteria in your gut. If probiotics are the seeds, then prebiotics is the soil, sunshine, and water that help bring them to life and keep them thriving. Prebiotic foods include:
- Dandelion greens
- Jerusalem artichokes
- Chicory root
- Bananas (especially green bananas)
Breathe in Microbes in Nature
One of the easiest and most profound ways to increase the microbial diversity in your gut is simply to spend time in nature, breathing in the air, and getting exposure to the earth, trees, flowers, and dirt. Live microbes live abundantly in nature, especially in areas kept clean like national parks, the beach, larger forests, mountains, lakes, and creeks. Simply spending time in nature will introduce an array of healthy microbes into your body.  So get outside!
Microbiome and Hormone Health: Summary
The gut microbiome plays a role in various bodily functions, including digestion, absorption, and assimilation of nutrients, immune regulation, brain health, and hormonal production. Microbial diversity has a cross-talk relationship with estrogen. Estrogen influences microbiome health and vice versa. Having a robust gut microbiome is vital to properly metabolizing estrogen. Estrogen also plays a crucial role in keeping the gut lining healthy and robust. Some of the key ways to promote microbial diversity include: avoiding anti-bacterial agents and harmful foods, increasing your consumption of probiotics and prebiotic foods, and getting out in nature to breathe in healthy microbes.
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Medical Disclaimer: This article is based upon the opinions of Dr. Daniel Pompa. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Pompa and his associates. This article has been medically reviewed by Dr. Charles Penick, MD for accuracy of the information provided, but Dr. Pompa encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional.