Hashimoto’s and Estrogen Dominance: How Hormones Play Off Each Other

Does Estrogen Dominance Complicate Hashimoto’s Disease?

How many times have you said, “Ugh, my hormones are so out of whack!”

My own hormones have been out of whack. Yep, mine.

So, this subject is near and dear to me.

In fact, I have spent most of my adult life working on hormone health - for many years for supporting my Hashimoto’s thyroid condition, in the past for promoting optimal progesterone levels for fertility, and especially today as I enter perimenopause and know firsthand the symptoms of estrogen dominance.

In my opinion, a healthy hormone foundation is so important to creating health in nearly every other aspect of your life!

But, wait, are hormones really out of whack? Or are they just out of balance?

What’s really going on?

When you feel this way (“I’m so hormonal right now!”) it could be a sign that what you really have is estrogen dominance (ED).

And ED does complicate matters if you also have Hashimoto’s disease.

Hormones work together and play off each other. (Because both Hashimoto’s and ED involve hormones and glands, the link between them is very strong.)

So, it’s important to start with a general understanding of estrogen and other hormones and their role in the body before you can fully grasp how a hormone imbalance may affect you.

And, how it affects your Hashimoto’s.

Hormones 101

When many of us hear the word “hormones,” we automatically think of the sex hormones, namely estrogen and testosterone. And we associate estrogen with women and testosterone with men.

While there is a basis for this, it’s also true that both men and women have both estrogen and testosterone. But these are not the only “sex hormones.”

And not all hormones are sex hormones.

The term hormones refers to a substance produced by any glands in the body. They serve many purposes, including regulating body temperature, balancing blood sugar, changing mood, triggering sleep and many, many more.

These hormones include thyroxine (thyroid hormone), insulin (blood sugar regulation hormone), adrenaline, cortisol (both are adrenal hormones), human growth hormone and leptin, plus some more you may have never even heard of.

But even if you just consider the sex hormones, estrogen and testosterone are both secreted by the ovaries and testes as well as the adrenal glands.

This means they are not exclusive to one gender.

Oh, and neither is progesterone.

Progesterone is generally considered a female sex hormone but is produced in men and is in fact a precursor to testosterone. It is also released by the ovaries and adrenal glands.

When we talk about estrogen, we are actually talking about a group of three kinds of hormones: estrone (E1), estradiol (E2), and estriol (E3).

They get grouped together and used interchangeably as a way to simplify talking about hormones.

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Hormone Imbalance in Women (Estrogen, Progesterone and Testosterone)

In women, it is important to have the right balance of estrogen and progesterone, as well as testosterone. When one gets too high, this leads to an imbalance.

Imbalance issues might include:

  • too high testosterone in women can be a risk factor in polycystic ovarian syndrome (PCOS)
  • when progesterone levels are too high, premenstrual syndrome (PMS) can become unbearable
  • imbalance in hormones also increases the risk of certain cancers

But in this blog, I will primarily explain estrogen dominance because of its important and all-too-common link to Hashimoto’s.

I have a lot to explain about hormones first - bear with me.

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The Hows & Whys of High Estrogen

In normal menstrual cycles, estrogen and progesterone increase and decrease at different points. In the weeks prior to ovulation, estrogen rises before dipping once ovulation has occurred.

During the last two weeks of the cycle, progesterone rises to balance with estrogen.

Women make three main types of estrogen: estradiol, estrone, and estriol.

Estradiol is the most common type found in non-pregnant women of childbearing age. Its main function is assisting with the monthly egg release from the ovaries.

Estrone, also produced in the ovaries, as well as fat cells, is the form found in women post-menopause.

Estriol occurs in abundance at pregnancy and is released by the placenta. Each has a role and will fluctuate throughout the menstrual cycle.

Women going through the first stages of perimenopause will often see estrogen become the more dominant hormone.

Although hormone decline as we age is normal, the imbalance can come when progesterone decreases at a greater rate than estrogen.

So, while we think of estrogen dominance as high estrogen, it can just as likely stem from low progesterone. This is most common in the start of menopause, but for some women can start as early as the mid-30s.

With the start of the peri-menopause and menopause journey, women may experience high levels of estrogen and low progesterone.

But many women also suffer from significantly low estrogen levels.

When we speak of ED, we must remember that it is not the overall numbers that cause this but high estrogen in comparison to progesterone.

Symptoms of estrogen dominance (ED) include:

  • A decrease in sex drive
  • Irregular menstrual cycles
  • Water retention or bloating
  • Swelling and tenderness of the breasts
  • Premenstrual headaches
  • Mood swings
  • Weight gain, especially around the midsection
  • Slowed metabolism
  • Brain fog or memory loss
  • Fatigue
  • Sleep problems
  • PMS
  • Hair loss
  • Cold hands and feet

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The Overlapping Symptoms Between Hashimoto’s & Estrogen Dominance

Yep, you’ll notice that some of these symptoms are pretty familiar if you have Hashimoto’s. Especially slower metabolism, brain fog, fatigue, insomnia and cold extremities.

That was me to a “T” at age 23 and I felt terrible.

While there may be no way to know exactly what has caused this imbalance in you, it is important to note some of the risk factors in estrogen dominance, such as:

  • Excess body fat
  • High stress
  • Low fiber in the diet
  • Impaired immune function
  • Environmental factors
  • Birth control pills or other exogenous hormones

The Role Of Body Fat in Estrogen Dominance

Now remember, estrogen and progesterone are both released by the ovaries and adrenal glands.

But only estrogen is also released by fat cells, causing an imbalance when there is excess fat.

In fact, when body fat is over 28% a woman’s risk of estrogen dominance goes up. That is because the more fat you carry, the more estrogen you produce and vice versa.

Fat cells are loaded with aromatase, an enzyme required for the biosynthesis of estrogen.

The higher your percentage of body fat, the more estrogen you can produce and the fatter you will be unless you stop the cycle through better nutrition, exercise and stress reduction steps.

The bottom line?

Although we of course need fat on our body to function, excess fat, especially around the abdominal area, can increase estrogen levels.

This is one of the main reasons why I use bio-impedance analysis testing in my office. Knowing body composition metrics is much more important than knowing the number one the scale alone as a measure of total health.

The Role Of Adrenal Hormones in Estrogen Dominance

The adrenal glands unfortunately have the huge task (among other things) of releasing adrenaline and cortisol, which are both stress hormones.

But, did you know that adrenals also help produce and regulate estrogen and progesterone?

Some of the same raw materials that makes up progesterone and estrogen are also used to make cortisol, which is the long-term stress hormone that gets you through hours, days or even weeks or more of stress.

Here’s the problem: progesterone can be put on the backburner when the body feels that cortisol is a higher priority.

If progesterone production declines, estrogen dominance can be the result, even if estrogen is not particularly high.

So, stress is a huge factor in hormone balance - because when stress hormones are elevated, it can lead to adrenal fatigue.

Adrenal fatigue does not allow for the body to have the sex hormones it needs.

Higher estrogen levels have also been found to raise cortisol levels, essentially making an existing imbalance worse by converting that progesterone into cortisol.

So - in review - the vicious cycle:

High stress + Higher body fat → Estrogen Dominance + Elevated Cortisol → Lowered Progesterone → High stress + Higher body fat → Estrogen Dominance

See, this is a cycle you want to break - and the first place to do so is through better stress management.

More on that later.

Thyroid’s Link to Estrogen Dominance

Ok, let’s circle back to your thyroid.

The late Dr. John Lee, who claims to have coined the term “estrogen dominance,” said that estrogen in high levels, suppresses thyroid function and the conversion of T4 to the active T3 form of thyroid hormone.

Wait, what?

Too much estrogen may slow down thyroid hormone conversion?

Yes, you read that right.

According to Dr. Lee, this fact is a major reason why hypothyroidism is much more common among women.

AND this explains why many women show signs of hypothyroidism as they start menopause or as soon as their hormones start to shift in perimenopause.

Mind blown.

Ok, now get this: progesterone (which may be too low in cases of estrogen dominance), cortisol and testosterone support healthy thyroid function.

Specifically, progesterone has been found to raise levels of free T4 (a form of T4 thyroid hormone that is not bound to proteins and circulates freely) and an enzyme called thyroid peroxidase (TPO) that helps makes T3 and T4.

Too little progesterone and testosterone may slow down thyroid hormone production and conversion?

Yes, you read that right.

One more thing: Excess estrogen can cause the liver to produce too much thyroid binding globulin (TBG), which is a protein that binds to thyroid hormones.

In healthy levels, TBG helps to transport those hormones and make them more efficient in the bloodstream.

But when in excess, TBG (due to ED) can decrease the amount of free thyroid hormones and make their transport through the body slower.

Too much estrogen may slow down thyroid hormone efficiency and transport?

Yes, you read that right.

I Have Hashimoto’s & Possibly Estrogen Dominance, Now What?

Test Your Hormones

If you suspect you have estrogen dominance or have found that you do have excess estrogen, there is plenty to consider in terms of what this means for your health, your thyroid and what you can do to try to balance your hormones.

First, it may be important to know how estrogen dominance affects your levels of thyroid hormones if you have Hashimoto’s.

Are your labs coming back abnormal, even though you are taking thyroid hormone medication?

Are your labs coming back normal but you are still feeling terrible?

I encourage you to speak to your physician about running some sex hormone labs in addition to your thyroid hormone labs.

That is where you might find the missing link.

Ideal Progesterone to Estrogen Ratios

Since we know that both estrogen and progesterone serve important roles in women’s bodies and health but that too much of either isn’t great, it can be helpful to know what a good ratio is. (Note: estrogen dominance is much more common than progesterone dominance)

The two hormones are tested in a panel that can be done with either saliva or blood. The ratio is called Pg/E2 (progesterone to estradiol). When divided, the ideal overall number should fall between 100 and 500.

For example, if a woman’s progesterone levels are 300 pg/mL and her estrogen is 1.5 pg/mL in a saliva test, her overall number is 200, which would be considered a healthy number.

Or in cases of a blood serum test, if her progesterone levels are 20,000 pg/mL and her estradiol is 100 pg/mL, she still has the same 200 number. (Progesterone is often given in terms of ng/mL but can easily be converted to pg/mL by multiplying by 1,000.)

Remember that doctors and other healthcare providers may have different numbers that they look for in patients. So, it is always advised to speak with your provider about any test results.

Saliva Hormone Testing

Saliva testing is an easy and noninvasive way of assessing your hormone balancing needs, and is proving to be the most reliable medium for measuring hormone levels.

In addition to measuring sex hormones, saliva hormone testing can also give accurate information about your cortisol levels, when drawn at four points during the day.

This gives clues about where the diurnal cortisol curve is. If cortisol is out of balance, then you can bet sex hormones are out of balance as well.

Remember, there is constant interplay between sex hormones, adrenal hormones, thyroid hormones - and many others!

Saliva hormone tests are offered to my clients where this type of testing is needed.

I interpret the results of your saliva hormone testing and explain your total sex hormone, adrenal and thyroid health picture.

Once we know what is out of balance, we know best how nutrition and lifestyle can help.

I suggest the following saliva hormone test for the clients I work with remotely: Salivary Hormone Panel by Diagnostechs. It costs $379 but is valued at over $600.

What's Being Tested:

Cortisol (4 samples - 24 hours)

The good folks at True Health Labs allow you to directly order labs that make the most sense for your health condition, allowing you to better participate in the overall management of your health.

If you do order these labs, be sure to take them with you to your next provider appointment.

Show them that you are willing to do what it takes to get the correct information for the best treatment plan possible.

Working with me through the customized Adult Advanced Program is the best way to utilize saliva hormone test results for optimal dietary and lifestyle enhancements.

Estrogen Dominance + Hashimoto's Can Impact Your Fertility

How does this combination of ED and Hashimoto’s affect your chances to get pregnant (if that is something you are aiming for)?

As you may already know from my previous posts, thyroid imbalances and Hashimoto’s in particular can greatly impact fertility. If you have Hashimoto’s and ED, it can be a double whammy.

During pregnancy, your body cranks estrogen production into overdrive. This hormone, which is vital in the development of female sex characteristics, also plays a part in establishing and maintaining pregnancy.

But in the postpartum phase, estrogen dominance is quite common. In fact, for many women, this is actually the time where ED begins and is very hard to reverse.

There are indications that ED is a factor in endometriosis, uterine fibroids and ovarian cysts, which can negatively affect fertility.

Progesterone, which is made in the ovaries, is hugely important for getting and staying pregnant.

It is a key hormone for the development and survival of an embryo, which is why there is a rise in it right after ovulation.

Because estrogen dominance can mean low levels of progesterone just as much as it means high levels of estrogen, during ED, progesterone levels may be affecting fertility.

As discussed earlier, estrogen levels can still be “normal” during ED if progesterone levels are low. This is especially true since progesterone can dip faster than estrogen does during perimenopause.

Detox for Hormone Balance

There is some really good news in all of this.

Nutrition and other lifestyle changes can have a HUGE impact on balancing these hormones in a gradual but sustainable and significant way.

A big lifestyle change that helps to restore healthy hormone balance is practicing daily detox.

The Liver & Hormones

The liver has a complex two-step detoxification process, which filters hormones and toxins in the bloodstream.

In phase one, the liver converts substances into toxic free radicals before they are converted to a water-soluble form in phase 2.

If phase 2 isn’t operating sufficiently, the toxic free radicals build up.

Both phases of liver detox must be in balance so proper elimination of waste can occur via sweat, urine, stool or vapor from the lungs.

An important role of the liver is to produce sex-hormone binding globulin (SHBG). This substance regulates the levels of circulating estrogen.

The liver also produces bile, which aids in elimination as it carries estrogen, and other waste via dietary fiber out of the body.

If fiber isn’t available due to dietary deficiency, the risk of toxic estrogen build up is increased. More about fiber in a bit.

Sometimes it takes several passes through the detoxification process for substances to be metabolized, adding extra stress to the liver.

There are many foods that help flush out excess estrogen, by means of this critical liver detoxification process.

There are also foods and substances which slow down liver detox.

What to Avoid to Prevent Hormone Imbalance


It has long been known that alcohol can cause an increase in estrogen levels, even in amounts as low as one drink per day.

What is a little less clear is what kinds of alcohol have the biggest effect.

Some studies have found wine to raise estrogen levels the most.

Decreasing or even eliminating alcohol in all forms from the diet can certainly affect your estrogen-progesterone ratio.

Hormones In Your Food

When we discuss balancing hormones, it is inevitable that we must discuss the hormones that can be in our foods.

We call these exogenous hormones, meaning they come from outside the body. Endogenous hormones are those that are made within the body.

If you are serious about finding that balance, then eating meats and other animal-based foods that come from clean, hormone-free animals is crucial.

Conventional meats, eggs and dairy can come from animals that have been given hormones, usually to help them grow faster.

When a food is labeled as organic or hormone-free, it means that the animal was never given any hormones for growth. (Poultry and pork are not allowed to be given growth hormones.)

As growth hormones are given to cows used in producing conventional (that is, non-organic) milk, and plus the inherent nature of milk being a by-product of pregnant and nursing cows, hormone levels in those cows are of course higher.

And those hormones do in fact end up in the milk.

Although this means that some hormones are naturally present, it doesn’t mean that it is healthy in cases of hormone imbalances in women.

Women with ED may find that dairy products can lead to an unhealthy hormone ratio.

Soy Products Impact Hormones

One place we may not consider looking for hormones in our foods is in soy products. But soy naturally contains chemicals called phytoestrogens.

These are plant sources of estrogen and soy is infamously high in these exogenous hormones.

Although clean, organic sources of soy have been used therapeutically for women going through menopause who have had estrogen level dips, soy can be problematic for those with a high estrogen-to-progesterone ratio.

The phytoestrogens can mimic our natural estrogens and in fact do too good a job.

Estrogen receptors seem to prefer these to our own estrogens, allowing our endogenous estrogen to continue to circulate.

If you’re thinking, “I don’t eat that much tofu; I’m not a vegetarian,” you may not fully understand just how much soy is everywhere.

Soy, in its many forms, is added to many processed foods.

It is often used to boost protein content and can be found in ingredient lists as isolated soy protein. It’s been used as cheap filler, especially since it began to be subsidized decades ago.

It’s even used in ground meat and sausage, salad dressings, baby formula, bread, chips and crackers.

Other Toxins

As if toxins in our meats and water isn’t scary enough, you also have to look out for them in the products we use every day.

There may not be actual hormones in your body products and cleaning supplies, but unfortunately plenty of other ingredients can disrupt hormones.

Bisphenol-A (BPA) is used in lots of packaging and is one of the worst offenders of what are called endocrine disruptors.

This means they can mimic, interfere with, bind to or block hormones and prevent them from doing their jobs.

BPA is found in many food containers, like cans, plastic water bottles, pizza boxes and (horrifyingly) baby formula containers.

Endocrine disruptors have been described as the toxins which may increase production of certain hormones; decrease production of others; imitate hormones; turn one hormone into another; interfere with hormone signaling; tell cells to die prematurely; compete with essential nutrients; bind to essential hormones; and accumulate in organs that produce hormones.

This is very problematic - not just for your total hormone balance - but also very critical to resolving the toxic influences on your thyroid gland.

Other endocrine disruptors that are found in everyday products or their packaging include:

  • Polychlorinated biphenyls (PCBs)
  • Phthalates
  • Glycol ethers
  • Perfluorinated chemicals (PFCs)

What to Include to Help Your Body Flush Out Excess Hormones

Liver Flushing Foods

Because the liver helps to flush excess hormones of all kinds from the body, foods that support the liver can aid in cases of estrogen dominance. (This is another reason why decreasing alcohol helps as well, since it is hard on the liver.)

It may not be the most popular food but it’s kind of a no-brainer that eating liver is great for your liver.

A very clean source of liver is extremely important since the liver is used for eliminating toxins. But if you can get it, make some pate and enjoy.

Other great liver-supporting foods include:

  • Eggs (pasture raised)
  • Citrus
  • Garlic
  • Dark leafy greens
  • Berries
  • Avocado
  • Cruciferous vegetables

Cruciferous vegetables, such as broccoli, cauliflower, kale, Brussels sprouts and mustard greens, are not only powerhouses when it comes to detoxifying.

They also contain a fascinating phytonutrient called diindolylmethane (DIM), which I’ll cover later in supplements.


As I mentioned earlier, one of the best things you can do to your diet for estrogen dominance is to make sure to include plenty of fiber.

Not only does fiber help the liver, it is great at getting rid of the excess estrogen circulating through your body.

Even after it’s done its job, hormones can continue traveling through the body in the bloodstream and even cause MORE problems than it did the first time in circulation.

Yes, eventually it will get reabsorbed.

But, all the more reason to consume plenty of fiber which loves to grab that active and inactive estrogen and help the body excrete it faster.

The best way to get fiber is make sure to eat a whole foods-based diet, free from processed and packaged foods (as much as possible).

This is because processing strips food of its fiber.

Vegetables and fruits are excellent sources of fiber, as are legumes, nuts, seeds and whole grains.

Water, Water, Water

Enough can’t be said for the power of water for flushing excess hormones of any kind from your body. Most Americans are dehydrated and may not even know it.

In a world full of sodas, juices, coffee and energy drinks, there is something to be said for keeping your favorite water bottle close at hand.

Unfortunately, our water sources are not always the cleanest these days.

And there are many indications that man-made chemicals are circulating in our drinking water systems. Yuck!

These include medications such as birth control pills that contain hormones! Double yuck!

Although I don’t advocate buying bottled water (both for the waste and the toxins that can seep from the plastic into the water), using a water filter whenever possible is highly recommended.

Supplements To Support Your Liver and Detoxification Pathways

There are a few nutritional formulas you can add to your daily regimen in order to best support your liver and detoxification pathways.

Diindolylmethane (DIM)

One nutrient that is getting a lot of attention lately is diindolylmethane, or DIM. DIM has been found to help break down estrogen.

A study from 2011 even found that supplementing with DIM helped balance estrogen levels specifically in those with thyroid disease.


Magnesium, which is often associated with relaxation and releasing muscles, has also been found to aid in the excretion of estrogen and helps with hot flashes and cramps.

Calcium D-Glucarate

Calcium D-glucarate, which is probably lesser known to you than magnesium, is a calcium salt and can be made within our bodies or found in food.

But supplementing with it regulates the metabolism of estrogen, meaning it can help for cases of too much or too little.

Calcium D-glucarate also promotes healthy detoxification by the liver.

Essential Fatty Acids

Essential fatty acids (EFAs) are fats that the body can’t make on its own and must be consumed.

This includes the ever-popular omega-3s, which are found in fish oil supplements and are extremely anti-inflammatory.

EFAs are also precursors for hormones. And like magnesium, they have been found to help with hot flashes, specifically in frequency.


Vitex, an herb also known as chaste tree, is excellent for restoring balance between estrogen and progesterone.

And it has long been used by midwives in cases of miscarriage caused by low progesterone.

Red Clover

Another herb, red clover, contains what are called isoflavones, which act like estrogens in the body but are not as potent and therefore can decrease some of the side effects of elevated estrogen.

Currently there is interest in the possibility of using red clover as an alternative to hormone replacement therapy.

Stinging Nettle

Lastly, there has been increased interest in stinging nettle, an herb found to inhibit an enzyme that promotes the conversion of testosterone into estradiol.

Lifestyle Habits for Hormone Balance

Resolving Stress Supports Hormones

As I’ve already pointed out, stress can be a factor in causing and sustaining hormone imbalances so it goes without saying that reducing stress can help bring balance to estrogen and progesterone.

Obviously, it is not always an option to get rid of what stresses us out (job, money, family, traffic, whatever it is that drives you nuts).

But how you allow those triggers to cause a reaction in you may be somewhat under your control.

Meditation, exercise and yoga can be potent stress-relievers and don’t have to take up too much of your time.

For others, talk therapy may be just the thing.

You may have to play around with what works for you.

For me, I have found that having a quiet and consistent bedtime routine EVERY night helps me combat stress, restore my adrenals, support production of melatonin for restful sleep and wake up feeling more refreshed.

It doesn’t have to be complicated. Just start practicing some self-care every day and see how it changes you!

Excellent Exercise To Release Your Stress

Not only can exercise help you release that stress from your mind and body, it can also build up your metabolism, promote weight loss and balance blood sugar, all things that also help with hormone balancing.

Exercise is excellent for promoting detoxification!

Even just 30 minutes of exercise five days a week has been found to reduce estrogen levels in premenopausal women.

Solving the Hashimoto’s & Estrogen Dominance Puzzle

There are many ways in which our hormones may get out of whack.

But the good news is that there are just as many steps you can take to help get both your thyroid and estrogen levels back on track.

It may sound daunting but each little step you take is a step in the right direction.

Nutrition and lifestyle changes for Hashimoto’s and estrogen dominance are well within your grasp. This article can help you get started.

If you want to take control of your total health and keep both your hormones (both reproductive and adrenal) and thyroid gland in balance, my Nourished and Renewed with Hashimoto's Program is a good place to embark on your healing journey.

Just remember that while the advice is general for anyone, I can also help you tailor those changes to suit your specific needs and your lifestyle.

When you have tried other avenues to resolve estrogen dominance, Hashimoto’s, or both - with little or no success and need a reboot - it’s time to start the Happy & Healthy Adult Program.

It’s easy to get rolling - book your first appointment with me today.

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The information on this website is for educational purposes only and should not be considered medical advice. This information is provided to help you make informed decisions about your health. It is not meant to replace the advice of your primary physician.

Choosing a holistic approach to health care through nutrition means choosing personal responsibility for your health care. Sara Peternell, MNT, is not liable or responsible for any harm, damage or illness arising from the use of the information contained herein or through any of the nutritional therapy programs available for purchase.

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