I recently read an article about concerns with the use of flaxseed in women with adenomyosis due to its estrogen activity. This article intrigued me since I have always promoted the use of this nutrient, so I did some research.
The reason that I promoted the use of flaxseed in women with adenomyosis is because I had tremendous symptom relief after adding flaxseed to my diet. At that time, I had been suffering terribly with severe pain, and I was desperate to find anything that would help me. I had been on all kinds of medications, none of which helped, and had several surgeries. I read up on the health benefits of flaxseed, and I was ecstatic when, after I added it to my diet, my pain level dropped dramatically.
I have since published a book, Adenomyosis: A Significantly Neglected and Misunderstood Uterine Disorder, and have included an entire chapter on the benefits of omega-3 fatty acids in the treatment of adenomyosis. Flaxseed contains very high levels of omega-3 fatty acids. Another chapter is dedicated to phytoestrogens, and flaxseed also falls into this category.
The concern with the use of flaxseed is that it contains a substance called lignans. Lignans are a type of phytoestrogen. Phytoestrogens are substances that can act like estrogen in the body. Many people are concerned that lignans may increase their estrogen levels and lead to further problems with adenomyosis since it is an estrogen-dependent disorder. A very reasonable concern, for sure.
The subject of phytoestrogens is a very complicated topic as I found out while doing research for my book. I found out that some phytoestrogens are not advised while others may actually help those with hormone-dependent disorders such as adenomyosis. Let me explain.
Phytoestrogens compete against our own natural (endogenous) estrogen for the estrogen receptor sites in our body. Estradiol is an example of endogenous estrogen. In general phytoestrogens are much weaker than endogenous estrogen. According to Seidl and Stewart, “the relative potency of phytoestrogens is, at most, only 2% that of estradiol.”¹ That is a general statement, however, and is not always the case as you will see below.
Proponents of the use of phytoestrogens argue that since they are so weak and they compete with our own estrogen which is much stronger, our estrogen levels should drop which would be good for hormone-sensitive disorders. However, recent research has shown that these substances act in different ways. In fact, a few phytoestrogens have, in fact, been found to be as strong as estradiol.
Some phytoestrogens are estrogen agonists, meaning that they increase estrogen levels. As stated previously, a few have been reported to be as strong as estradiol. However, some estrogens are antagonists, meaning that they decrease estrogen levels. Black cohosh is an example of an estrogen antagonist. A study by Rebbeck et al. has shown the use of black cohosh in women with breast cancer may have a protective effect since this herb has been shown to have anti-estrogenic effects.²
The most important thing to know is just because a nutrient is known to be a phytoestrogen, that doesn’t necessarily mean that it’s bad for women with hormone-sensitive conditions. It all depends on the specific phytoestrogen and if it works in an agonist or antagonist fashion. Now, let’s look at flaxseed specifically.
The few studies out there regarding flaxseed and estrogen activity have been inconsistent. However, evidence seems to be pointing in the direction that flaxseed may actually be beneficial in hormone-sensitive disorders. However, much more research needs to be done to confirm these findings. Many experts still warn about the use of flaxseed in hormone-sensitive disorders.
- A study was performed where women with recently diagnosed breast cancer ate one muffin per day for 40 days that contained 25 mg flaxseed. The researchers noted a reduction in tumor growth during this time.
- A case-controlled study in the U.S. showed that women with this highest intake of lignans had the lowest risk of endometrial cancer and ovarian cancer.
- Another study showed a reduction of breast tumor growth and metastasis in rats that consumed a diet high in lignans.
- According to WebMD, “some early laboratory and animal research suggests that flaxseed might actually oppose estrogen and might be protective against hormone-dependent cancer.”³
These findings are suggestive of an estrogen-antagonist action in the lignans found in flaxseed. However, if you are still worried about this nutrient, there are other options, such as fish oil which contain high levels of omega-3 fatty acids without the controversial lignans. Omega-3 fatty acids have been found to be very beneficial in the treatment of endometriosis.
- A study done by Covens, Christopher, and Casper in 1988 showed that “dietary supplementation with fish oil, containing the n-3 polyunsaturated fatty acids EPA and DHA can decrease intraperitoneal PGE2 and PGF2-alpha production and retard endometriotic implant growth in this animal model of endometriosis”.4
- Another study done by Missmer, Chavarro, Malspeis, Bertrone-Johnson, and Hornstein in 2010 states “…those women in the highest fifth of long-chain fatty acid consumption were 22% less likely to be diagnosed with endometriosis compared with those with the lowest fifth of intake…”5
Hopefully more studies will be done soon on lignans and their effects on estrogen levels so these preliminary findings can be confirmed or disproven. We need clear answers so we can deal with these hormone-related disorders, especially adenomyosis, effectively.
If you want to try flaxseed to see if it helps you, the following brand is the kind that I purchased years ago when I tried it (click on image to purchase through Amazon):
For more detailed information on phytoestrogens, omega-3 fatty acids, and flaxseed, check out my book, Adenomyosis: A Significantly Neglected and Misunderstood Uterine Disorder. Click on image to purchase through Amazon.
¹Seidl, M.M. & Stewart, D.C. (1998). Alternative treatments for menopausal symptoms: Systematic review of scientific and lay literature. Canadian Family Physician, volume 44. Retrieved from http://www.europepmc.org/backend/ptpmcrender.fcgi?accid=PMC2278270&blobtype=pdf
²Rebbeck, T.R., Troxel, A.B., NOrmal, S., Bunin, G.R., DeMichele, A., Baumgarten, M.,…Strom, B.L. (2007). A retrospective case-control study of the use of hormone-related supplements and association with breast cancer. International Journal of Cancer, 120, 1523-1528. doi: 10.1002/ijc.22485
4Covens, A.L., Christoper, P., & Casper, R.F. (1998). The effect of dietary supplementation with fish oil fatty acids on surgically induced endometriosis in the rabbit. Fertility and Sterility, 49(4), 698-703. Retrieved from http://www.researchgate.net/publication/20324462_The_effect_of_dietary_supplementation_with_fish_oil_fatty_acids_on_surgically_induced_endometriosis_in_the_rabbit
5Missmer, S.A., Chavarro, J.E., Malspeis, S., Bertrone-Johnson, E.R., & Hornstein, M.D. (2010). A prospective study of dietary fat consumption and endometriosis risk. Human Reproduction, 25(6), 1528-35. doi:10.1093/humrep/deq044