Phytoestrogens: to eat soy or to not eat soy?


Yes, this meal is safe to eat. Photo courtesy of United Soybean Board.

Are phytoestrogens like soy safe to eat?

This is a common question in my office. People tell me they have heard soy has strong estrogen-like effects that will worsen PMS or PCOS. They have heard that soy is bad for the thyroid. Soy might even disrupt men’s hormones and cause them to grow breasts. These stories are circulated in the media, particularly online and social media, often enough that I appreciate why people ask the question: are phytoestrogens like soy safe?

The TLDR answer is: yes, soy and other phytoestrogens are safe for women and men to eat.  In many cases, they may even be protective for women experiencing problems related to high or low estrogen levels.

What are phytoestrogens?

Phytoestrogens are plant compounds that have estrogen-like properties. This is because their shapes loosely resemble the shape of a naturally occurring estrogen molecule, estradiol. But whereas estradiol fits in an estrogen receptor perfectly, like a key in a lock, phytoestrogens do not. Phytoestrogens are more like a toy key that you give a toddler to play with. Phytoestrogens gently nudge estrogen receptors, simultaneously creating a small amount of estrogenic activity and blocking the receptor from receiving stronger stimulation from other sources.

And this is where the therapeutic effect of phytoestrogens comes from: in situations where estrogen levels are already too high, phytoestrogens protect estrogen receptors from overstimulation. And in situations where estrogen levels are uncomfortably low, like menopause, the gentle nudge against an estrogen receptor may provide just enough activity to relieve discomfort.

In other words, phytoestrogens modulate estrogen levels. When natural estrogen levels are high phytoestrogens have a net anti-estrogen effect, and when natural estrogen levels are low their effect becomes more estrogenic.

Where do phytoestrogens come from?

There are 2 main types of phytoestrogen: isoflavones and lignans.

  • Isoflavones: a plant molecule found in the plant family Fabacea (bean family), especially soybeans.
    • Highest concentrations in: edamame or whole soy beans, tempeh, tofu, miso, soy butter
    • Other sources: chickpeas, peanuts
  • Lignans: a component of insoluble fiber, found in many plants.
    • High concentrations in: flax seeds, sesame seeds, cereal brans (e.g. oat bran, rice bran)
    • Other sources: whole grains (wheat, millet, rye, barley), legumes, nuts, asparagus, grapes, kiwi, lemons, oranges & pineapple

Dietary lignans depend on healthy gut flora to metabolize or change them into a form where they are biologically active. And it is not just the estrogen receptor activity that makes lignans healthy, they also have beneficial effects on the cardiovascular system.

Phytoestrogens and Digestive Health:

If phytoestrogens were a cure-all for estrogen related problems, it wouldn’t be a secret. But they do have a measurable and meaningful impact on many hormonal imbalances. For example:

A 2015 meta-analysis of 15 studies done on phytoestrogens and menopausal symptoms shows that they are able to reduce frequency of hot flashes compared to placebo.

A 2012 quasi-randomized study of 146 women with PCOS in Italy showed that use of a phytoestrogen lignan isolate for 3 months reduced levels of DHEA-S and testosterone and improved lipid profiles by reducing triglycerides and LDL (aka “bad cholesterol”) levels.

Clinically, I suspect that one of the keys to how people respond to phytoestrogens is contingent on the state of their digestive health. It is known that lignans, for example, need to undergo transformation by healthy gut bacteria to become fully active as phytoestrogens in the body. And the balance between healthy and unhealthy gut bacteria is also likely the lynch pin for whether people find foods containing phytoestrogens beneficial for their hormonal and metabolic balance, or a cause of gas, bloating and fatigue.

Not everyone responds well to soy and other foods rich in phytoestrogens. Digestive problems are common among people who do not tolerate soy and other legumes well.  One reason for this is the fructo-oligo-saccharide content of legumes, recall that the legume family is the plant family most well known for producing phytoestrogens, are fodder for the fermenting bacteria responsible that cause the digestive condition SIBO (small intestine bowel overgrowth).

This underscores why digestive health is such a critical piece of the puzzle in finding hormonal balance for many women. Fortunately, there are tests available to evaluate digestive health, including tests for SIBO to see if there is a bacterial overgrowth that requires treatment before phytoestrogens can be successfully tolerated and metabolized, as well as tests to determine the presence, abundance and diversity of healthy gut bacteria.

About the author:

Miranda Marti, ND, LAc is a body positive naturopathic physician and acupuncturist specializing in the holistic treatment of PCOS and other chronic conditions affecting hormonal, digestive and mental health.

Is plastic disrupting my estrogen?

BPA-free plastic food containers and utensils remain ubiquitous in our kitchens. Photo by Miranda Marti, ND.

The investigative journalism magazine, Mother Jones, just published a compelling story on the presence of xenoestrogens in BPA-free plastics.

Xenoestrogens, synthetic chemicals that are capable of stimulating estrogen receptors in human (and other animal) bodies, are a growing concern worldwide. Exposure to xenoestrogens can come from the food supply, as they accumulate in the fat of animals that are exposed to some to them, primarily through herbicides and pesticides (atrazine is the most notorious), and then find their way into milk, butter, and meat. They can also come from direct contact with certain plastics, or from food  stored in plastic containers. The now-banned BPA-containing plastics were the most notorious offenders, but now we have strong reason to believe that they are not the only ones.

This topic is of significant interest to those of us at Whole Life Medicine who care for women with diseases of estrogen-dominance, such as PCOS, fibroids, endometriosis.  Is part of what’s driving these disease processes environmental exposure from plastics? And if so, how can we limit that exposure to protect our health?

I have a personal stake in this game. I am one of those estrogen-dominant women. I even have genetic test results that show my body is a slow estrogen metabolizer. What this means is that I don’t make a full compliment of the enzymes that break estrogen and estrogen-like chemicals down and inactivate them, so they spend a longer time in circulation with the opportunity to stimulate my estrogen receptors, which in the long run can cause tissues that are sensitive to estrogen to be overactive and create health problems.

I’d also like to state very clearly that I am not “anti-chemical” by any stretch of the imagination. I’ve had too many years of chemistry, organic chemistry and biochemistry education to fear “chemicals” or even “synthetic chemicals” generally; I understand that chemicals generally speaking make up pretty much everything we are and interact with and do not inherently pose a threat to health. But as an Environmental Studies-Biology major at Whitman College, I began getting curious if some of the synthetic chemicals we interact with on a daily basis like plasticizers, specifically phthalates, might not be interacting with our bodies’ hormone system in ways that could be harmful to our health.

Years after undergrad, my interest was reignited after reading Nena Baker’s The Body Toxic. In this book Baker, an investigative journalist, considers the evidence about what is and isn’t known about common industrial and synthetic chemicals that haven’t been subjected to rigorous safety screening; and whether multiple exposures from daily living might lead to a “chemical body burden” that is beyond the scope of individual safety profiles to comprehend. For example, if over the course of the day I am exposed to ScotchGuard and food heated in plastic and the  plastic in my toothbrush, those exposures together could accumulate to levels  that are dangerous, even if individually each exposure would be considered safe by the safety data on ScotchGuard, the plastic in my tupperware and the plastic in my tooth brush. Xenoestrogens feature prominently in the book as a case study for chemicals needing further human safety data.

What I took away from The Body Toxic is that BPA-contianing plastic is worth avoiding, but that BPA is probably not the end all and be all of  my xenoestrogen exposure because all plastic may be suspect, which is indeed the point that the recent Mother Jones article makes. And that foods that are moist or have an appreciable fat content are the ones most likely to leach xenoestrogens from their plastic containers into the food I would consume, so those are the foods I can prioritize creating, storing and consuming from non-plastic containers. I also read labels of all products that I put on my skin to avoid those containing “phthalates.”

To the right is a picture of my stash of containers for storing left-overs, prepared foods and things I don’t want to wilt in the refrigerator.

My glass food storage collection. Photo by Miranda Marti, ND

And after making those changes around 4-5 years ago, which proved to be sustainable in my life in terms of time and money spent on them, I considered myself reasonably protected. Certainly I still receive exposures to xenoestrogens but my goal isn’t 100% avoidance, it’s harm-reduction.

The new news on BPA-free plastic, however, has me wondering if that is enough. While the data on exposure to plastics and causation of estrogen-related diseases is not strong enough for me to offer much proscriptive advice. What I will say is probably in everybody’s best interest to avoid xenoestrogen exposure from plasticizers is:

  • Store moist or fat-containing foods in metal, ceramic or glass containers, not plastic.
  • Do not heat foods in plastic containers, no matter how microwave safe.
  • Check labels in grooming products to avoid anything with “phthalates.”
  • Be aware anything listed as “fragrance” may be diethyl phthalate (DEP).
  • Avoid air fresheners: many brands contain phthalates but are not required to list them on the label.
  • Choose ethylene vinyl acetate (EVA) over PVC plastics in toys and building materials, as EVA does not require plastic softeners, polyethylene or other plastic polymers.
  • Read the Mother Jones article on BPA-free plastics and other well-researched work on the issue, and check to make sure they cite their sources if they make strong claims about risk or safety.

Beyond that, I think it’s up to the individual to decide what’s right for them in terms of time and money costs, as well as availability. Here are some of the issues I’ve started thinking about in my pantry, which currently looks like this:

My plastic-filled pantry. Photo by Miranda Marti, ND.

What amongst this plastic-wrapped shelf must I worry about? The reality is, I don’t know that I can make the switch for everything that comes in plastic packaging. So here are the top three daily-consumed foods I’m considering making changes for re: purchasing and storing habits:

  • I love sunflower seed butter and use it almost every morning with breakfast, but the brand I’ve been buying lately from Trader Joe’s is in a plastic container, which is concerning because of the product’s high fat content. Perhaps it’s time to switch to a brand that comes in glass. This should be easy to do with the occasional trip to another store, such as PCC or Whole Foods.
  • For the past few years I’ve used coconut flour, which is high in fiber, to make my morning waffle. Ordinarily I wouldn’t worry too much about grains or flours in plastic packaging because these products are generally dry and have very little fat that could leach xenoestrogens, but coconut flour is an exception due to it’s fat content. I’d like to buy and store it in non-plastic packaging, but I don’t recall ever seeing it offered outside of a plastic bag. Perhaps there is a bulk buying option at PCC where I could bring my own glass or paper container….but honestly, will I? Those are extra steps to take that I might not be motivated to actually take, but I will at least explore my options.
  • Almonds are another food I consume frequently, going through at least a pound per week. I usually buy a 1 lb bag from Trader Joe’s or a 3 lb bag from Costco. Almonds are not moist, but they do have a considerable fat content. I know for sure I could buy the in bulk in a non-plastic container, but the price difference for doing so would be considerable compared to what I’m used to paying.

As I continue to peruse my pantry over the next several days, I’m sure I’ll come across many more oft-consumed items that are packaged or stored in plastic to consider. It’s an on-going process, and I’ll be sure to let you know if I come up with any brilliant ideas to avoid plastics without great inconvenience cost or inconvenience.

This post is courtesy of Dr. Miranda Marti.

The Hormonal Poetry of Sex and Love

Photo courtesy of the Orange County Archives.

The hormones most directly related to love, bonding, romance and sexual arousal can be remembered through the apt acronym POET: prolactin, oxytocin, estrogen and testosterone.

While both men and women respond to these hormones, they do so in different ways and with different results.  There is currently a great article on Medscape on the topic, Miriam E. Tucker. Hormonal ‘POETry’ Key to Valentine’s Day Romance. Medscape. Feb 13, 2014 (note: to access the full article a medscape log in is required, but an account is free to set up and open to anyone over the age of 18).

If you don’t have time for the log-in, however, here is a quick run-down of the role these hormones can play in men and women.


Prolactin “generally has no effect on libido in normally cycling women, but it can suppress sexual desire when levels are too high, such as in women who are breastfeeding, have prolactin-producing tumors, or are taking medications that affect dopamine pathways.”

Oxytocin, “the ‘cuddly hormone,’ induces uterine contractions and facilitates milk ejection after childbirth. Elevated levels appear during orgasm, but its role in female sexual desire isn’t as clear as it is with men.”

Estrogen “directly affects vaginal engorgement and lubrication, and it regulates female genital tissues’ “receptivity” to sexual activity.”

Testosterone ” also correlates with female sexual desire and satisfaction.”


Prolactin  “likely is responsible for the immediate decline in sexual desire and the onset of sleepiness following orgasm” and may be an indicator of satiety.

Oxytocin “recent studies suggest that oxytocin in men increases their empathy for and speed of response to facial expression cues; increases activity in brain areas associated with arousal, reward, memory, and social bonding ; and increases their willingness to share emotions.”

Testosterone, contrary to popular belief “high testosterone levels do not correlate with sexual function. However…small decreases in testosterone can affect sexual desire and satisfaction, as can visual cues and relationship issues.”

This blog post comes courtesy of Dr. Serena McKenzie.

Unmanageable periods? Could be endometriosis.

March is Endometriosis Awareness Month.

Common sites of endometriosis in the pelvis and abdomen.

Do you know someone whose life becomes unmanageable around the time of her period due to intense pain or strange symptoms, like allergic reactions, digestive problems or fatigue? The problem could be endometriosis.

Endometriosis is a painful condition that can cause digestive symptoms, abnormal menstruation and infertility. It occurs when the tissue that lines the uterus, the endometrium, starts growing elsewhere in the body. This most often occurs within the pelvis around the ovaries, but can happen anywhere – even the brain!

Pain that is suggestive of endometriosis includes pelvic and lower abdominal pain or low back pain that occurs:

  • during menses that does not feel better with the use of anti-inflammatories, like ibuprofen, or other types of conservative pain control, like heating pads
  • between periods but feels likes menstrual cramps
  • before, during or after sex
  • with bowel movements and urination, especially during menses

Other unusual symptoms of endometriosis are:

  • allergies, migraines or fatigue that are worse during menses
  • difficult bowel movements or alternating constipation and diarrhea that does not respond to standard IBS treatment or dietary changes
  • bloating, nausea and vomiting during menses

The pain and other symptoms associated with endometriosis have a reputation of being hard to diagnose and treat through conventional medicine alone. That’s why all of our physicians are trained to view the body holistically and treat not just the symptoms of endometriosis, but the underlying cause of hormonal imbalance and inflammation.

One of the major reasons endometriosis occurs is due to an imbalance of estrogen levels in the body. Many doctors address this imbalance primarily through the use of additional hormones, such as birth control pills, and pain management medications. This treats the symptoms of endometriosis, but it doesn’t treat the cause.

Estrogen Balance and Nutrition:

Broccoli and other members of the Brassica family of vegetables help promote healthy estrogen balance.

One important avenue for treating endometriosis is to focus on foods that support efficient hormone metabolism and avoiding non-organic vegetables. meats, dairy and other foods that may be a significant source of hormone exposure.

“It’s not just the hormones in the cows, but the pesticides on the fruits, vegetables and grains that can influence estrogen levels in endometriosis. You have to focus on the diet to treat the disease.” – Dr. Mary O’Connell, gynecologist

There are also a number of herbal protocols that can help the body balance estrogen and progesterone levels on its own to reduce symptoms and progression of endometriosis.

For pain management, our doctors provide guidance on how to develop an anti-inflammatory eating plan, how to effectively use supplemental anti-inflammatory oils and herbs for long-term pain management. Our clinic also has acupuncturists who are skilled in treating pelvic and low back pain.

If you know someone whose life becomes unmanageable around the time of their menses, share this blog post or have them schedule an appointment to evaluate their symptoms and assess their hormone balance.

This post is courtesy of Dr. Miranda Marti.

Picture of common sites of endometriosis courtesy of Tsaitgaist via the Creative Commons Attribution-Share Alike 3.0 Unported license.

Picture of broccoli courtesy of La Grande Farmers’ Market via Creative Commons Attribution 2.0Generic license.

Monthly Migraines: Causes and Cures

Monthly migraines

Image courtesy of Pierre Willemin, Creative Commons.

This post on the role of estrogen in monthly migraines is courtesy of Dr. Miranda Marti.

For many women a monthly migraine is an estrogen-associated migraine.  Particularly if the timing of the migraine is predictable, such as around the start of menses.

Estrogen-associated migraines occur because of the effects a sudden withdrawal of high estrogen levels has on serotonin levels and blood vessels. This can be a natural occurrence within a woman’s menstrual cycle, it can be a scheduled withdrawal from estrogen-containing medications (such as the placeholder pills in an package of oral birth control) or it can be accidental from a missed dose of any estrogen-containing medication, including hormone replacement therapy.

Stopping the pain

So, what can be done about monthly migraines?  Quite a lot, from symptom relief to cure. Our doctors, including gynecologist Mary O’Connell and our naturopath physicians, all specialize in balancing hormone levels to stop the pain of monthly migraines.

For women using any form of hormonal birth control, one of the first places to start is to ask: does it contain estrogen? Is there a lower dose estrogen or estrogen-free option that could work for me?

There are also many non-drug approaches to managing estrogen-related migraines that can provide pain relief, some as simple as supplemental magnesium taken during specific times of the menstrual cycle.

Curing the pain

To address the root cause of why a woman’s body is responding to estrogen this way, one must look at her body as a whole and evaluate not just how much estrogen is being delivered, but how the estrogen is being processed and eliminated.

This is holistic medicine and it is something that our naturopathic physicians excel at.

For all women with estrogen-associated migraines, the question to ask is: how efficient is my estrogen metabolism? Factors affecting estrogen metabolism and breakdown include the liver detoxification, digestion, and possibly estrogen receptor stimulation via pesticide exposure.

Liver Metabolism

Many women don’t realize that their body has to break down estrogen in the liver the same way it does many other biologically active chemicals, like caffeine and alcohol. Some people have an inherently lower capacity to do this than others because of their genetics, and some people have a lower capacity to do so because their liver has a high burden of exposure to many substances needing detoxification.

Signs that your estrogen metabolism could be improved:

  • Sensitivity to or intolerance to: caffeine, alcohol or medications
  • Other symptoms of high estrogen levels, particularly PMS: premenstrual weight gain or bloating, mood swings, cramping, breast tenderness


After estrogen has been broken down into metabolites in the liver, the body moves these waste products via bile into the intestines so that they can be eliminated from the body in a bowel movement. Constipation or sluggish digestion can interfere with this process significantly because it gives the body time to reabsorb some of the estrogen metabolites back into circulation. Laxatives are not a long-term solution to this problem.

Women with monthly migraines and infrequent bowel movements (fewer than 5 per week) or frequent bouts of constipation could benefit from addressing their digestive concerns. Our approach is to focus on healthy non-laxative stimulation of digestive function, primarily using foods and fiber.

Pesticide exposure

Some pesticides are suspected to have the ability to stimulate our estrogen receptors and disrupt our distort our normal hormonal function, as is discussed in my blog post on organic foods.

Effectively treating and eliminating monthly migraines is about more than hormone and medication management. It is about being able to look at the body as a whole and recognize which systems can bring the body back into a stable and sustainable hormonal balance.