It’s almost impossible to avoid every potential source of xenoestrogens in modern life, that’s why it’s important to prioritize them based on which ones are the most harmful and which lifestyle changes require the least effort for the most benefit (like switching to glass storage containers). But for those that manage to slip by, there’s still a way to address them. In this article we’re going to look at variety of foods that fight xenoestrogens, and how they do it.
There are three main categories here, three ways that food and other aspects of the diet can help fight xenoestrogens. First, they can help the body get rid of excess estrogens and xenoestrogens, like by aiding estrogen metabolism. Second, they can help with the effects of excess estrogens, treating various symptoms of estrogen dominance. And third, they can help block xenoestrogens at the source by binding to estrogen receptors in the body. That may seem counterintuitive, but in effect a weak estrogen activating an estrogen receptor takes up a “slot” that would otherwise have been taken by a much more potent xenoestrogen. This ultimately reduces the estrogenic impact on your body. These foods we’re about to look at don’t represent a complete diet on their own, they are just one aspect of a healthy diet. The goal here isn’t to maximize testosterone, just to minimize excess estrogen.
First up, let’s take a look at cruciferous vegetables. These are a family of vegetables that have a lot in common with each other, both in appearance and in the nutrients found in them. Some examples of cruciferous veggies are:
- Bok Choy
- Brussel Sprouts
- Collard Greens
- Mustard greens
These vegetables are widely known for their health benefits, but one of their lesser known properties is their ability to fight xenoestrogens. They are rich in glucobrassicin and glucoraphanin, which the body processes into a number of xenoestrogen fighting substances.
Indole-3-carbinol comes from glucobrassicin when the body breaks it down. Cruciferous vegetables contain high levels of that glucobrassicin, which means they’re good sources of indole-3-carbinol. That’s great, but what does indole-3-carbinol do? Perhaps most significant is its ability to increase the body’s ability to fight estrogen sensitive cancers, like breast cancer. The i3c (indole-3-carbinol) can slow or stop the growth of the cancer, and help kill it 1. This effect is increased with help from genistein, an isoflavonoid found in the phytoestrogen soy. In addition, it seems to also directly increase the body’s resistance to forming new tumors 2.
Just as the body makes i3c out of glucobrassicin, the body can also make 3,3′-Diindolylmethane from the indole-3-carbinol. This is very handy because the 3,3′-Diindolylmethane, also known as DIM for short, has anti-xenoestrogen properties of its own.
3,3′-Diindolylmethane, or DIM, is the “active ingredient” in most of i3c’s ability to fight xenoestrogens. But on top of all that, DIM can function as an antiestrogen, effectively reducing the effect of estrogen on the body 3. How exactly it does this is currently unknown, but one possibility is that DIM interferes with signal transduction pathways. In effect, this means it helps the body break down estrogen faster, reducing its impact. DIM supplements have also been studied for their potential to fight breast cancer, and it looks promising. 30 days of DIM supplementation reduced known markers for breast cancer risk 4, which effectively means it made the subjects less likely to get breast cancer.
Cruciferous vegetables also contain glucoraphanin. It’s found in all cruciferous vegetables, but particularly in broccoli sprouts and cauliflower. Just like the glucobrassicin, which is made into indole-3-carbinol and then into DIM, this glucoraphanin is processed into sulphoraphane. For the body to turn glucoraphanin into sulphoraphane, it needs an enzyme called myrosinase. In fresh broccoli you can get plenty of this from chewing or cutting it, but when it’s cooked at a high temperature 5, or frozen 6, almost all of the myrosinase is lost. And with it, the potential sulphoraphane from the broccoli, or other cruciferous vegetable. Fortunately, there’s a few answers to this. The simplest is to just eat fresh broccoli without cooking it too much, or just steaming it lightly. The goal is to not get it too hot, because that’s what breaks down the myrosinase. If you buy frozen broccoli, consider mixing it with a bit of ground up radish. This was found to restore the presence of myrosinase, and in turn restoring the potential sulphoraphane 7. Another option is to grow your own at home and even indoors with a kit like this.
The role of sulphoraphane in fighting xenoestrogens is very similar to DIM – it aids estrogen metabolism 8. This mean it helps your body process estrogen and get rid of it quicker, especially if there’s an excess of it. This helps get rid of it before it can do too much damage.
PROMOTING GUT FLORA
Although it may seem a little weird, there is in fact a flourishing (hopefully) ecosystem that lives inside you. There are vast colonies of bacteria that live in your guts, and interact with each other in a very complex manner. In a way, they “eat” what you eat and live that way. But they’re not parasites, in fact they play a large role in your health, and even interact with your body’s hormonal balance. Healthy gut flora means a healthy body (and maybe even a healthy mind 9) which means that a diet that supports a healthy population of them helps you. Intestinal microflora play a key role in breaking down estrogens 10 and xenoestrogens. Your diet plays a huge role in the health of your gut flora 11 12.
For example, there is a particular strain of bacteria that can live in the gut, known as Lactobacillus acidophilus. It can play a very big role in helping eliminate estrogen from the body. This one is found mainly in yogurt, miso, and tempeh. There is an enzyme, called Beta-glucoronidase, that “frees” estrogen that was soon to be eliminated from the body via waste, which allows it to be reabsorbed into the body. That’s no good if you’re trying to reduce the estrogen in your system. But with a diet high in Lactobacillus acidophilus, the presence of this enzyme in the gut is reduced significantly 13, which means more estrogen being eliminated faster.
So what helps gut flora thrive?
Fermented foods have traditionally been a staple in human diets in many cultures, but they’ve mostly fallen out of popularity in most modern Western diets. Fermented foods are foods like:
Most people haven’t heard of most of those, so don’t worry if you haven’t either. What these fermented foods have in common is that they support certain beneficial bacteria populations, the sorts that are good to have living in your belly. Eating fermented foods supports healthy gut flora 14, since they have a probiotic effect (the opposite of antibiotics). Fermented foods (sauerkraut in particular) have even been found to help with breast cancer 15 which may mean they also help with other estrogen sensitive cancers, like prostate cancer. Aside from helping metabolize estrogens, a healthy gut flora has a ton of other health benefits like helping with depression 16, autism 17,and even weight loss 18.
Probiotics are good for the same reasons fermented foods are. They support healthy gut flora, which in turn supports a healthy body and mind. Taking probiotic supplements is generally a lot more convenient than actually eating fermented foods, but the trade-off is that they’re probably gonna be a lot less effective. Still, they can be a useful supplement to fill in, temporarily or otherwise. One of the most common probiotics is the previously mentioned Lactobacillus acidophilus, so that’s a good place to start. Probiotics like this one are made in such a way that more of the beneficial bacteria survives passing through the stomach, which means more of it reaches your intestines. And that’s the whole point.
You may be surprised to see fiber on this list, but it plays a surprisingly large role in fighting xenoestrogens. For starters, a high fiber diet helps the intestines work more efficiently, keeping things moving along. What this does is prevent any estrogens in the waste from being reabsorbed by the body. Studies have shown that high fiber diets reduce estrogen 19. Many foods that fight xenoestrogens contain fiber.
But that’s not all, fiber also aids a process in the body called enterohepatic circulation 20. This process is the circulation of bile between the intestines and the liver – where it is produced. This helps the body clear fat-soluble substances (like estrogen) from the bloodstream, then bile drops it off to be eliminated. The body uses fiber to create more bile, to replenish and replace it as the bile gradually becomes thicker and more polluted with the substances it’s trying to eliminate from the body. It’s kind of like the oil in a car, as it cycles it gets dirtier and thicker, and needs to be replaced eventually so the engine can continue running properly. Eating fiber helps with this “oil change” and keeps things running smoothly. Without it, the bile becomes increasingly thick and polluted, which is not good for you at all. It can cause or contribute to a range of health issues 21 it also lets things accumulate in your bloodstream that should have been eliminated already. Things like excess estrogen.
Third, there is a type of fiber called lignins (not to be confused with lignans) that binds to estrogen in your body 22 effectively neutralizing it. When the lignins bind to the estrogens, the estrogens can no longer “fit” in estrogen receptors, so they have no effect. These lignins can be found in flax seeds, beans, and lentils.
Last but not least, fiber also supports gut flora 23 , which is good because that helps the body process foods more efficiently. The gut flora can effectively digest things that the human digestive system alone cannot, which helps us get more nutrition from the foods we eat.
So where can you get fiber in your diet? Some of the best sources are:
- Black Beans
- Brussels Sprouts
- Flax Seeds
Eating foods like these is the best way to get a proper fiber intake. There are also fiber supplements you can take, the most popular probably being psyllium husk. Powdered supplements work best if you’re supplementing fiber, because you can take a bit with every meal. This is far more effective than a single large fiber supplement once a day. You can sprinkle some of the powder on your meal if it’s low in fiber otherwise, and this will help your body digest it well. But if you just take a single fiber pill a day, it’ll only help with the meal you take it with, plus it might be hard on your digestive system to get such a massive dose.
Lignans are phytoestrogens, which are natural substances that mimic the effect of estrogen – but are usually much weaker. Lignans function as very weak estrogens and your body has a limited amount of estrogen receptors, so when a weak phytoestrogen binds to one of these receptors it potentially prevents a more potent estrogen or xenoestrogen from binding there. Which is what we’re looking for in an environment full of xenoestrogens. You can find lignans in a whole host of foods including:
- Sesame seeds
- Flax seeds
- Sunflower seeds
Let’s take a closer look at a couple of these.
Certain fish are high in Omega-3 fatty acids, which is very important to the healthy function of the human body. You’ll find them in fatty fish, like tuna, salmon, herring, and sardines. Fish oil supplements have exploded in popularity in recent years thanks to claims to a vast range of health benefits, though they’re a bit exaggerated. And to be fair, omega-3 fatty acids have been found to be helpful for many things including asthma 24 and recovering from heart attacks 25. But for the purpose of fighting xenoestrogens, the important bit is that fish oil contains lignans.
Some fish, like tuna, salmon, and sardines are good sources of selenium. Although selenium deficiency is relatively uncommon these days, it may be lacking in some modern diets, especially those that are heavy on processed foods. Selenium not only plays a role in testosterone production, but also has an anti-aromatase function 26. Aromatase is an enzyme that converts some androgens, like testosterone, into estrogen. So less aromatase means less estrogen.
Flax seeds are one of the richest sources of lignans that you can find. Even among relatively densely lignan-packed seeds, flax seeds come out on top. But that’s not all, flax seeds also show promise in fighting hormone-sensitive cancers like breast cancer 27 and prostate cancer 28. These two cancers, among others, are associated with high levels of estrogen, so it follows that anything that reduces the amount of estrogens or their influence in the body could potentially help alleviate the risk.
Some fruits, like pomegranate and grapes have an anti-aromatase effect. Aromatase is an enzyme that can turn androgens, like testosterone, into estrogen. Which means, basically, that reducing aromatase reduces estrogen. Pomegranates showed a a significant amount of anti-aromatase activity 29, not to mention some other benefits like improving heart health 30. Grapes have also been found to possess an anti-aromatase function 31. In addition, grapes are also an excellent source of a polyphenol called resveratrol. Resveratrol is also an aromatase inhibitor 32. On top of that, it also has anti-aging properties 33.
All of that sounds pretty good, but keep in mind that the dosages in these studies were reached using extracts and other concentrates. It would be pretty rough to get the same amount just eating the fruit plain. That said, just eating the fruit should still have the same effects, just not as powerfully as demonstrated in the research. So don’t expect any miracles, but they will still be a beneficial part of your diet. Or you can try using the extracts directly, like cooking with grape seed extract oil.
(Header image credit to Coyau at Wikimedia Commons)
- Auborn KJ, et al “Indole-3-carbinol is a negative regulator of estrogen.” Journal of Nutrition 2003 Jul;133 ↩
- Dashwood, Rod H.; Arbogast, D.N.; Fong, A.T.; Pereira, C.; Hendricks, J.D.; Bailey, G.S. (1989). “Quantitative inter-relationships between aflatoxin B1 carcinogen dose, indole-3-carbinol anti-carcinogen dose, target organ DNA adduction and final tumor response”. Carcinogenesis. 10 (1): 175–81. ↩
- Rajoria, Shilpi, et al “3,3′-Diindolylmethane Modulates Estrogen Metabolism in Patients with Thyroid Proliferative Disease: A Pilot Study” Thyroid 2011 Mar; 21(3): 299–304. ↩
- Dalessandri KM, Firestone GL, Fitch MD, Bradlow HL, Bjeldanes LF. “Pilot study: effect of 3,3′-diindolylmethane supplements on urinary hormone metabolites in postmenopausal women with a history of early-stage breast cancer.” Nutrition and Cancer 2004;50(2):161-7. ↩
- Matusheski NV, Juvik JA, Jeffery EH. “Heating decreases epithiospecifier protein activity and increases sulforaphane formation in broccoli.” Phytochemistry 2004 May;65(9):1273-81. ↩
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- Yang L, et al “Reduced formation of depurinating estrogen-DNA adducts by sulforaphane or KEAP1 disruption in human mammary epithelial MCF-10A cells.” Carcinogenesis 2013 Nov;34(11):2587-92 ↩
- Evrensel A and Ceylan ME “The Gut-Brain Axis: The Missing Link in Depression” Clinical Psychopharmacology and Neuroscience 2015 Dec; 13(3): 239–244. ↩
- Gorbach SL “Estrogens, breast cancer, and intestinal flora.” Reviews of Infectious Diseases 1984 Mar-Apr;6 Suppl 1:S85-90. ↩
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- Goldin BR, Swenson L, Dwyer J, Sexton M, Gorbach SL. “Effect of diet and Lactobacillus acidophilus supplements on human fecal bacterial enzymes.” Journal of the National Cancer Institute 1980 Feb;64(2):255-61. ↩
- Hemarajata P, Versalovic J. “Effects of probiotics on gut microbiota: mechanisms of intestinal immunomodulation and neuromodulation.” Therap Adv Gastroenterology. 2013;6(1):39-51. ↩
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