Estrogen Dominance Might Not Be What You Think - Dr. Michael Ruscio, DC

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Estrogen Dominance Might Not Be What You Think

Key Takeaways:

  • Estrogen dominance is more about low progesterone than too much estrogen.
  • Diagnosis usually happens based on symptoms because it’s hard to test for low levels of estrogen or progesterone.
  • Symptoms of imbalance in every direction overlap and include things like breast tenderness, PMS, and irregular periods.
  • Progesterone plays an important role in mitigating estrogen in the body.
  • The connection between gut health and hormonal health is a two-way street, so addressing one can help address the other.
  • Diet and lifestyle changes, including eating more cruciferous vegetables and reducing stressors can impact both gut health and hormonal health.

Estrogen dominance is an area where there’s been some confusion and misguided information. I’d like to clear that up in this article. I have some concerns about the messaging around estrogen that resulted from the NIH’s Women’s Health Initiative study. The outcomes of the study may have resulted in some unnecessary vilification of estrogen, which can, unfortunately, affect the way we as healthcare professionals treat women experiencing hormonal imbalance.

Hormonal imbalance can mean a lot of things and result in a wide array of symptoms, especially for women. Understanding the interplay between estrogen and progesterone and the way high and low levels of both can affect your health is really important when it comes to addressing both the symptoms and the root cause. Simply prescribing progesterone is almost never the right course of action.

My goal is to clear up the confusion by clarifying the definition and potential symptoms of estrogen dominance, unpacking the potential root causes, and clarifying that both female hormones play vital roles in a healthy reproductive system—there’s no reason to vilify estrogen.

Estrogen Dominance Doesn’t Always Mean High Estrogen

Estrogen dominance isn’t a medical term, but it refers to when estrogen levels are out of balance—“unopposed”—by progesterone levels in the body. It can occur and lead to unwanted symptoms whether or not estrogen levels are abnormally high.What differentiates high estrogen from estrogen dominance is that in the latter, there’s not enough progesterone to balance the estrogen. In fact, you can have estrogen dominance even if levels of estrogen are low but progesterone levels are even lower—too low to balance the remaining estrogen (such as in perimenopause) [1].

Estrogen Dominance

Especially in thin women displaying symptoms of estrogen dominance, it’s possible their estrogen levels are actually normal or maybe even low. In cases like these, rebalancing estrogen with progesterone using gentle herbs can often solve the problem. Much to the detriment of their overall health, women are often pushed into taking unopposed progesterone (progesterone without any additional estrogen to balance it out), which can lead to its own set of undesirable consequences. If you think you might be experiencing symptoms of low estrogen, keep reading to find some good tips to help you balance your hormones.


The problem with addressing low levels of both hormones is that it’s hard to test for them, especially in menstruating women. Therefore, estrogen dominance tends to be diagnosed based on symptoms rather than lab results. Because accurate testing is difficult, we often overestimate the incidence of “progesterone deficiency” and over-attribute certain symptoms to it. Interestingly, low progesterone can often manifest as symptoms of low estrogen.

These symptoms may include disruptions in [2]:

  • Bone density, which can contribute to weak or brittle bones
  • Uterine lining and cervical tissue, which may contribute to low sex drive, painful intercourse, irregular periods, no periods, vaginal dryness and thinning of vaginal tissue
  • Breast tissue, which may contribute to breast tenderness and breast cancer
  • Heart and blood vessels, which may contribute to hot flashes, night sweats, headaches before or during your period, difficulty concentrating, moodiness and irritability
  • Brain/sleep patterns, which may contribute to insomnia, fatigue, difficulty concentrating, moodiness and irritability, and weight gain, especially as belly fat
Estrogen Dominance

In contrast, abnormally high estrogen levels are easy to detect in lab results, but not by a person’s symptoms. It’s possible to have both high estrogen and high progesterone, such as what occurs with granulosa cell tumors that secrete a lot of both [3]. Women with breast cancer can also have unusually high progesterone levels that can oppose unusually high levels of estrogen. This could happen, for example, in the case of metabolic syndrome, which is a collection of symptoms that includes obesity, high blood sugar, and high blood pressure [3]. 

What Causes High Estrogen and Estrogen Dominance?

In many cases, the same factors can lead to both excess estrogen and estrogen dominance. These factors can be lifestyle related, such as stress, drinking too much alcohol, excess body fat, or exposure to xenoestrogens (BPA and phthalates in plastics and certain pesticides) [1, 2, 3, 4]. And they can also be due to medications like hormone replacement therapy (HRT) or birth control. Finally, they can occur because of health conditions like liver dysfunction or granulosa cell tumors [1].

Metabolic issues like PCOS and gut dysbiosis are both potential causes and symptoms of estrogen dominance [4, 5, 6]. This means that while we know these issues are related, we don’t know which causes which, and more research needs to be done at the intersection of endocrine and metabolic health. That being said, it stands to reason that improving your gut health with diet and probiotics, along with key lifestyle changes can help move the needle when it comes to balancing hormones (more on that below).

When high estrogen (with enough progesterone to balance it) and estrogen dominance (too little progesterone to balance the estrogen) arise from similar causes, their symptoms manifest depending on where progesterone levels are relative to estrogen. In other words, the level of progesterone will affect the way the imbalance shows up in the individual.

Symptoms of Estrogen Dominance

The symptoms that result from the imbalance of estrogen and progesterone (whether estrogen is too high or not) often overlap with those of perimenopause. They may include [1, 2, 3, 4, 5, 6, 7]:

  • Premenstrual headaches or “menstrual migraines”
  • Mood swings
  • Signs of low progesterone:
    • Difficulty sleeping
    • Short cycles (21-24 days)/abnormal timing of periods
    • Spotting
    • Increased bloating
    • PMS
  • Unusually heavy periods
  • Reproductive cancers
  • Infertility
  • A PCOS (Polycystic Ovarian Syndrome, which is related to metabolic syndrome) diagnosis
    • Hair loss/male-pattern baldness
    • Acne, especially in the first half of the menstrual cycle
    • Weight gain in the mid-section
    • Body hair on chest, abdomen, jaw, and back
    • Absent or irregular periods
    • Enlarged ovaries
    • Skin tags
    • Thick, dark patches of skin on the back of the neck, armpits, and under breasts
  • Cyclic breast tenderness or pain, or fibrocystic breasts, especially in the second half of the menstrual cycle
  • Uterine fibroids
  • Weight gain around the hips and backside
  • Hot flashes and/or night sweats

Some of these symptoms are cyclical and timed with the menstrual cycle. Sometimes conventional doctors will prescribe hormonal birth control (HBC) to cover up these symptoms, but that doesn’t address the issue at the root, and can sometimes make matters worse.

Furthermore, HBC isn’t without risk or side effects. These may include an increased risk of blood clotting, mood imbalances, Crohn’s disease, fungal overgrowths, problems with thyroid hormone, and problems with libido and clitoral stimulation.

The Role of Progesterone

Estrogen isn’t the lone hormone in women’s reproductive systems. Just as important (but not as popular or well-researched) is progesterone, which serves to keep estrogen levels in check so they don’t go overboard and promote tumor growth, especially breast cancer [8]. The balance of estrogen and progesterone also helps maintain healthy bone density, uterine lining and cervical tissue, breast tissue, heart and blood vessels, brain function, and sleep patterns [8]. When the hormones are imbalanced, you can have any of the symptoms listed above.

It may be tempting to simplify estrogen dominance as progesterone deficiency, but not all progesterone deficiency manifests as estrogen dominance. In other words, it’s possible to have low estrogen and progesterone if your progesterone is still high enough to oppose whatever estrogen you have.

Extreme and prolonged stress, over-exercise and excessive calorie restriction, and thyroid problems can all result in low levels of both hormones as well.

The Gut-Hormone Connection: A Functional Approach

Estrogen Dominance

I mentioned above that, while more research is needed to determine a definitive causal relationship between gut health and hormonal health, some good evidence does exist. It’s worth proceeding as if health in these two areas is a two-way street. And by that, I mean we should treat improving gut health as one of the strategies to help improve hormonal health.

There’s a good chance that the gut and hormones work together as either a vicious or virtuous circle, considering the various examples of interrelationship between the two. For example, many women experience IBS symptoms—bloating, diarrhea or constipation, or abdominal pain—during their menstrual periods, indicating that a shift in hormones may trigger IBS [9].

We also know that female hormone imbalance often occurs secondary to a gut imbalance. Preliminary evidence seems to link inflammation in the gut, dysbiosis, impaired detoxification, and nutrient absorption directly to hormonal imbalance [5, 6, 10]. Furthermore, poor fat digestion, gut dysbiosis, and low microbial biodiversity in the female reproductive tract can all negatively impact female hormonal balance [3, 11, 12, 13].

We’ve seen a lot of positive results with a gut-centric approach to hormonal health in our clinic. This is especially true when paired with herbs and supplements that are designed to help balance hormones and some simple dietary shifts. Simple changes like adding more healthy fats and cruciferous vegetables (broccoli, kale, Brussels sprouts, etc) into your daily diet, increasing phytoestrogens like flaxseed, and cutting back on greasy and sugary foods are a great place to start.

A Word on Stress

Your body experiences and processes physical stress as well as mental and emotional stress. When you eat poorly (processed foods, too much sugar, too much alcohol, etc), it causes inflammation in your gut, which eventually leads to an imbalance of bacteria that favors the unhealthy strains. It may also be the case that you have particular sensitivities to certain foods or types of foods like dairy, gluten, or high FODMAP foods that can also create inflammation. The unhealthy strains cause more inflammation, and a cycle begins that leads to physical stress.

When stress is continuous (chronic stress), your body reallocates materials it would otherwise use to make sex hormones to produce cortisol (a stress hormone) instead, which leads to an increase in middle body weight and is linked to insulin resistance. High levels of stress have also been shown to increase gut permeability (leaky gut) [14, 15].

Thrive With Balance

Estrogen isn’t the enemy. It’s a vital piece of the reproductive puzzle, and it’s necessary for the female body to function properly. It simply needs to be in balance with progesterone, and both need to be in adequate supply all around.

Understanding your symptoms and what they mean about your health is an important first step in debunking the idea that estrogen is bad, and that taking progesterone will solve your problems. By making lifestyle changes to reduce the amount of stress, both in your life and on your body, adding in a probiotic, and tweaking your diet, you’ll already be well on your way to getting your hormone levels back into balance.

But if you’re looking for a more tailored approach, reach out to our clinic to schedule a consultation. We would love to help you.

➕ References
  1. High Estrogen: Causes, Symptoms, Dominance & Treatment [Internet]. [cited 2022 Mar 22]. Available from:
  2. Low Estrogen: Causes, Symptoms, Diagnosis & Treatment [Internet]. [cited 2022 Mar 14]. Available from:
  3. Cable JK, Grider MH. Physiology, Progesterone. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2021. PMID: 32644386.
  4. Estrogen Dominance – Whole Health Library [Internet]. [cited 2022 Mar 18]. Available from:
  5. Fuhrman BJ, Feigelson HS, Flores R, Gail MH, Xu X, Ravel J, et al. Associations of the fecal microbiome with urinary estrogens and estrogen metabolites in postmenopausal women. J Clin Endocrinol Metab. 2014 Dec;99(12):4632–40. DOI: 10.1210/jc.2014-2222. PMID: 25211668. PMCID: PMC4255131.
  6. Baker JM, Al-Nakkash L, Herbst-Kralovetz MM. Estrogen-gut microbiome axis: Physiological and clinical implications. Maturitas. 2017 Sep;103:45–53. DOI: 10.1016/j.maturitas.2017.06.025. PMID: 28778332.
  7. Ong M, Peng J, Jin X, Qu X. Chinese herbal medicine for the optimal management of polycystic ovary syndrome. Am J Chin Med. 2017 Mar 30;45(3):405–22. DOI: 10.1142/S0192415X17500252. PMID: 28359195.
  8. Prior JC. Women’s reproductive system as balanced estradiol and progesterone actions—A revolutionary, paradigm-shifting concept in women’s health. Drug Discovery Today: Disease Models. 2020;32:31–40. DOI: 10.1016/j.ddmod.2020.11.005.
  9. Meleine M, Matricon J. Gender-related differences in irritable bowel syndrome: potential mechanisms of sex hormones. World J Gastroenterol. 2014 Jun 14;20(22):6725–43. DOI: 10.3748/wjg.v20.i22.6725. PMID: 24944465. PMCID: PMC4051914.
  10. Goedert JJ, Jones G, Hua X, Xu X, Yu G, Flores R, et al. Investigation of the association between the fecal microbiota and breast cancer in postmenopausal women: a population-based case-control pilot study. J Natl Cancer Inst. 2015 Aug;107(8). DOI: 10.1093/jnci/djv147. PMID: 26032724. PMCID: PMC4554191.
  11. Delgado BJ, Lopez-Ojeda W. Estrogen. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2022. PMID: 30855848.
  12. Chen C, Song X, Wei W, Zhong H, Dai J, Lan Z, et al. The microbiota continuum along the female reproductive tract and its relation to uterine-related diseases. Nat Commun. 2017 Oct 17;8(1):875. DOI: 10.1038/s41467-017-00901-0. PMID: 29042534. PMCID: PMC5645390.
  13. Łaniewski P, Ilhan ZE, Herbst-Kralovetz MM. The microbiome and gynaecological cancer development, prevention and therapy. Nat Rev Urol. 2020 Apr;17(4):232–50. DOI: 10.1038/s41585-020-0286-z. PMID: 32071434.
  14. Vanuytsel T, van Wanrooy S, Vanheel H, Vanormelingen C, Verschueren S, Houben E, et al. Psychological stress and corticotropin-releasing hormone increase intestinal permeability in humans by a mast cell-dependent mechanism. Gut. 2014 Aug;63(8):1293–9. DOI: 10.1136/gutjnl-2013-305690. PMID: 24153250.
  15. Karl JP, Margolis LM, Madslien EH, Murphy NE, Castellani JW, Gundersen Y, et al. Changes in intestinal microbiota composition and metabolism coincide with increased intestinal permeability in young adults under prolonged physiological stress. Am J Physiol Gastrointest Liver Physiol. 2017 Jun 1;312(6):G559–71. DOI: 10.1152/ajpgi.00066.2017. PMID: 28336545.
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