Your digestion and microbiome influence your hormone issues in a significant way. This article will explain why they may be the missing link in premenstrual symptoms, irregular cycles, and everything in between.
“I didn’t know there was a connection between my hormones and my digestion.”
I know, right?
That’s why I’m excited to write this article. Women living with hormonal irregularities that present in the regularity of their cycle or as premenstrual symptoms such as cramping, bloating or unexpected emotional changes typically present with associated digestive symptoms either at the onset of their flow or across the whole cycle.
Often, I move towards correcting the menstrual cycle by correcting those same digestive symptoms.
Let’s look at how and why that works so often. We’ve been learning so much about the bidirectional relationship between digestion and many other systems over the last five to ten years.
In just the initial articles on this website, we’ve already looked at the link between digestion and the brain, immune system, the skin and chronic pain.
That’s not to mention the bacteria that occupy the digestion and the effects that different species of probiotics have. And this is where we are going to start.
The bacteria in digestion play a role in balancing the amount of oestrogen in the body.
And here we introduce the oestrobolome. The oestrobolome refers to the section of the microbiome that breaks down or metabolises oestrogen.[1] The bacteria that form part of this group play a vital role in phase three oestrogen clearance and circulation, two components that play a significant role in your menstrual cycle.
The liver is responsible for the first two phases, so let’s look at them first.
Oestrogen travels around the body in the blood. Once it reaches the liver, the liver inactivates and changes oestrogen into a water-soluble form, ready to leave the body. This new form of oestrogen is removed either through the bile in your stool or the urine. The process in the liver that does is called conjugation.[2] Think of the liver and conjugation as the sequence of events that wraps up oestrogen, ready to send out of the body.
Probiotic bacteria, such as Bifidobacterium species, are integral to the oestrobolome, and this process due to the presence of an enzyme called beta-glucuronidase.[3]
If you are new to how enzymes work, just think of the old TV adverts (if you’re that old) that used to boast about the enzymes in the washing powder that break down stains. In the case of this enzyme, beta-glucuronidase, its activity can reverse the conjugation process and cause the oestrogen, originally wrapped up to leave the body, to be unwrapped and sent back into the bloodstream.[4]
This sequence of events isn’t just crucial for balancing your menstrual cycle but for other oestrogen-related conditions such as metabolic syndrome, cardiovascular disease, anxiety, depression and Alzheimer’s disease.[5]
Here’s how I explain what beta-glucuronidase does to patients.
Imagine yourself on the way to the airport. Once an activated oestrogen molecule that’s done your vital work for the body. Now deactivated and ready to leave the body, you’ve gone through the liver and got your boarding pass to leave.
You reach the gate in the colon and the bowel and board your flight, which happens to be stool airlines (stay with me here). Now on the flight, your seat belt is fastened, and you’re flicking through the airline magazine about the top ten new destinations deactivated oestrogens are travelling to this year.
Then all of a sudden, a staff member named beta-glucuronidase comes to your seat and asks to escort you off the flight.
“My apologies, ma’am, it seems we’ve had to cancel your deactivation and trip out of the body today. My job is to escort you off the flight, activate you and send you back into the bloodstream.”
This recirculation can then lead to higher levels of circulating oestrogen. However, it doesn’t stop there.
Your hormones work on cue and feedback loops, so higher or lower circulating oestrogen levels can have a ripple effect on the body.
What we’ve illustrated here is one side of the story. Beta-glucuronidase activity can contribute to lower levels of oestrogen. This diminishing level occurs when the bacterial diversity in the digestion reduces, and with it, the number of bacteria contributing to the beta-glucuronidase activity.[6]
This change in bacterial diversity is called dysbiosis. Dysbiosis refers to a bacterial community that doesn’t have the right balance of bacteria to fulfil the everyday functions like managing the oestrogen levels in your blood. Diet, stress age and medications such as antibiotics can all sustain this imbalance over time.[7]
Antibiotics, mainly, have been found to affect levels of oestrogen directly. This effect is due to the medications’ effect on clearing the bacteria that create beta-glucuronidase. Women on a five or six-day course of antibiotics had their oestrogen levels measured to begin quantifying this effect. This small study confirmed that both urine and stool oestrogen levels increased, suggesting lower levels in the body.[8]
In contrast to the conditions caused by higher circulating oestrogen levels, lower oestrogen levels contribute to obesity, metabolic syndrome, cardiovascular disease, and cognitive decline.[9]
Women with Polycystic Ovarian Syndrome (PCOS) have particular characteristics in their gut bacteria.[10]
Estimates suggest that an average of ten per cent of women live with PCOS, depending on the region studied.[11]
PCOS is well-known to have a connection with insulin resistance. So much so that women living with PCOS can find it challenging to maintain their body composition and weight. New ideas suggest that specific bacteria in your gut can either manage this or make it worse.
For example, a genus (a way defining types of bacteria) called Dorea, measured via comprehensive stool testing, can positively influence BMI, glucose, and insulin levels.[12]
An undesirable form of bacteria called gram-negative bacteria may also play a role due to its presence in digestion alone. These particular bacteria secrete a molecule called lipopolysaccharides which induce inflammation, insulin resistance and obesity.[13] All of which are sustaining factors in PCOS.
Compounding this, women living with PCOS have significantly lower diversity counts when compared to healthy controls.[14] This lower diversity level means that the microbiome within the digestion could be a sustaining factor for some women looking to solve their PCOS.
It doesn’t stop there, though. The vaginal microbiome seems to play a central role in menstrual pain.[15]
Yep, between forty-five and ninety-five per cent of women will suffer some form of menstrual pain throughout their lives, depending on the region.[16]
Initial studies suggest that a commonly found probiotic genus, Lactobacillus, could hold the answers to easing pain symptoms that disrupt women’s lives monthly.
For those new to the term “microbiota”, the easiest way to think of it is the range of different bacteria and other microorganisms that populate a particular area. In this case, we are talking about the vaginal and reproductive tract.[17]
Studies have begun exploring this further and have found that higher levels of vaginal Lactobacilli bacteria were associated with lower inflammatory markers.[18] This effect reinforces research showing that Lactobacillus species create anti-inflammatory responses, blocking chemicals that cause inflammation in the vaginal tract, which should directly influence menstrual pain symptoms.
A quick note here. Notice I mentioned the word “should” in the last sentence. I’ve added this note because there haven’t been any definitive studies proving that increasing Lactobacilli bacteria assist with menstrual pain. Yet. A proof of concept study came out at the beginning of this year, so I’m betting we’ll see another connection between probiotic bacteria and menstrual symptoms!
This connection to probiotic bacteria and menstrual pain could open gateways to understanding endometriosis better.[19]
A study looking at the prevalence of IBS in over five thousand women with endometriosis found that IBS was two and a half times more likely to be diagnosed at the same time![20]
Studies have connected low Lactobacilli species and high levels of gram-negative bacteria to endometriosis. But we are yet to know exactly how significant this role is.
Once again, the connection reinforces the relationship between the bacteria in the digestion, microbiome and menstrual and hormone issues.
Over time, I hope to write a more in-depth article exploring the vaginal microbiome and how managing the delicate bacterial environment can unlock much more than we’ve covered today. Conditions like urinary tract infections and fungal infections come to mind as examples.
Just another way the digestion and microbiome link together to help you with your hormone issues.
As I mentioned at the beginning of this article, I have seen patients whose menstrual cycles have completely disappeared for differing reasons. Things return to regular programming post treating the bacterial environments of their small and large intestines. It’s pretty miraculous, and this article intended to introduce some of the concepts that explain why treating the digestion and the microbiome can be beneficial for your hormone issues. Only time will give us better research to understand the connection’s full potential.
For now, though, we’re moving into a fascinating new phase exploring the digestion, microbiome and hormone issues and menstrual conditions —one which may hold the key to unlocking a common digestive and hormonal picture that I see regularly.
Hope this helps.
References
[1] 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):djw029. Published 2016 Apr 22. doi:10.1093/jnci/djw029
[2] Plottel SC, Blaser MJ. Microbiome and malignancy. Cell Host Microbe. 2011;10(4):324-335.
[3] Zengul AG, Demark-Wahnefried W, Barnes S, et al. Associations between Dietary Fiber, the Fecal Microbiota and Estrogen Metabolism in Postmenopausal Women with Breast Cancer. Nutr Cancer. 2021;73(7):1108-1117. doi:10.1080/01635581.2020.1784444
[4] He S, Li H, Yu Z, et al. The Gut Microbiome and Sex Hormone-Related Diseases. Front Microbiol. 2021;12:711137. Published 2021 Sep 28. doi:10.3389/fmicb.2021.711137
[5] Williams GP. The role of oestrogen in the pathogenesis of obesity, type 2 diabetes, breast cancer and prostate disease. Eur J Cancer Prev. 2010;19(4):256-271. doi:10.1097/cej.0b013e328338f7d2
[6] 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
[7] Belizário JE, Faintuch J. Microbiome and Gut Dysbiosis. Exp Suppl. 2018;109:459-476. doi:10.1007/978-3-319-74932-7_13
[8] Adlercreutz H, Pulkkinen MO, Hämäläinen EK, Korpela JT. Studies on the role of intestinal bacteria in metabolism of synthetic and natural steroid hormones. J Steroid Biochem. 1984;20(1):217-229. doi:10.1016/0022-4731(84)90208-5
[9] 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
[10] Lüll K, Arffman RK, Sola-Leyva A, et al. The Gut Microbiome in Polycystic Ovary Syndrome and Its Association with Metabolic Traits [published correction appears in J Clin Endocrinol Metab. 2022 May 17;107(6):e2660]. J Clin Endocrinol Metab. 2021;106(3):858-871. doi:10.1210/clinem/dgaa848
[11] Giampaolino P, Foreste V, Di Filippo C, et al. Microbiome and PCOS: State-of-Art and Future Aspects. Int J Mol Sci. 2021;22(4):2048. Published 2021 Feb 19. doi:10.3390/ijms22042048
[12] Lüll K, Arffman RK, Sola-Leyva A, et al. The Gut Microbiome in Polycystic Ovary Syndrome and Its Association with Metabolic Traits [published correction appears in J Clin Endocrinol Metab. 2022 May 17;107(6):e2660]. J Clin Endocrinol Metab. 2021;106(3):858-871. doi:10.1210/clinem/dgaa848
[13] Cani PD, Amar J, Iglesias MA, et al. Metabolic endotoxemia initiates obesity and insulin resistance. Diabetes. 2007;56(7):1761-1772. doi:10.2337/db06-1491
[14] Lindheim L, Bashir M, Münzker J, et al. Alterations in Gut Microbiome Composition and Barrier Function Are Associated with Reproductive and Metabolic Defects in Women with Polycystic Ovary Syndrome (PCOS): A Pilot Study. PLoS One. 2017;12(1):e0168390. Published 2017 Jan 3. doi:10.1371/journal.pone.0168390
[15] Chen CX, Carpenter JS, Gao X, et al. Associations Between Dysmenorrhea Symptom-Based Phenotypes and Vaginal Microbiome: A Pilot Study. Nurs Res. 2021;70(4):248-255. doi:10.1097/NNR.0000000000000510
[16] Iacovides S, Avidon I, Baker FC. What we know about primary dysmenorrhea today: a critical review. Hum Reprod Update. 2015;21(6):762-778. doi:10.1093/humupd/dmv039
[17] Marchesi JR, Ravel J. The vocabulary of microbiome research: a proposal. Microbiome. 2015;3:31. Published 2015 Jul 30. doi:10.1186/s40168-015-0094-5
[18] Amabebe E, Anumba DOC. The Vaginal Microenvironment: The Physiologic Role of Lactobacilli. Front Med (Lausanne). 2018;5:181. Published 2018 Jun 13. doi:10.3389/fmed.2018.00181
[19] Bailey MT, Coe CL. Endometriosis is associated with an altered profile of intestinal microflora in female rhesus monkeys. Hum Reprod. 2002;17(7):1704-1708. doi:10.1093/humrep/17.7.1704
[20] Seaman HE, Ballard KD, Wright JT, de Vries CS. Endometriosis and its coexistence with irritable bowel syndrome and pelvic inflammatory disease: findings from a national case-control study–Part 2. BJOG. 2008;115(11):1392-1396. doi:10.1111/j.1471-0528.2008.01879.x
