ground flaxseed (not flaxseed oil)

rosyFL

Is anyone familiar with using ground flaxseed to include in our diets to help prevent BC?  I'm a little confused because I'm reading different things about it.  I know that any type of soy is a big no-no. 

leaf

I am not a physician or a nutritionist, but I can do a Pubmed search (papers that have been peer reviewed). As far as I know there are no studies in Pubmed that directly measure consumption of ground flaxseed and examine whether or not breast cancer incidence decreases. A study like that would probably take quite a bit of time.  So some papers have looked at indirect markers of breast cancer risk.

All of these studies (when they looked at humans) used normal women in the general population, not women who are at increased risk of breast cancer due to family history or LCIS or another cause.

This 2011 paper said 25gm/day x 1month ground flaxseed increased the amount of endostatin (as does tamoxifen).  Endostatin is thought to decrease the blood supply to tumors.  Tamoxifen, unlike ground flaxseed, also seems to decrease the levels of VEGF and angiogenin in the breast, which also can increase blood flow to tumors.  http://www.ncbi.nlm.nih.gov/pubmed/21984941

This 2010 paper found that 7.5-15gm/day ground flaxseed did *not* substantially increase certain estrogen metabolites in the urine, so they concluded flaxseed does not seem to alter breast cancer risk at least by this mechanism.  http://www.ncbi.nlm.nih.gov/pubmed/20099191  In contrast, this 1999 paper, using up to 10gm/day ground flaxseed concluded that flaxseed may have a chemoprotective effect.http://www.ncbi.nlm.nih.gov/pubmed/10368815

This 2008 paper found a 7.5-15gm ground flaxseed/day diet decreased the levels of estradiol, estrone, and testosterone, especially in overweight/obese women. http://www.ncbi.nlm.nih.gov/pubmed/18791924

I don't know too much about nutrition, but from these papers, I don't see anything that suggests that ground flaxseed consumption would *increase* the risk of bc.  So, from this info, I would guess that ground flaxseed won't increase your bc risk, but I don't think there's enough evidence  now to know whether or not ground flaxseed will actually decrease your bc risk.

********

I am no expert about soy either, but at least this one study says epidemiological studies looking at soy and breast cancer risk have had inconsistent results.  http://www.ncbi.nlm.nih.gov/pubmed/21113655 

So from the very little I've read, it seems like there aren't enough studies to really say if ground flaxseed will decrease one's risk of breast cancer, but I don't see evidence that it would hurt either.  (I would personally only consider taking pesticide-free flaxseed; I don't know if there are a lot of pesticides in flaxseed.  I know I can get organic flaxseed locally.)

LScott63

My naturopaths favorite saying is "its all about the poop" ... she said ground flaxseed (not oil) is a great source of fiber to help keep things moving.  So many of the meds are constipating so this helps keep things healthy.

jenn333

My UCLA integrative onc advises me to take 2 tablespoons of ground flaxseed daily.  I put it in my rice protein shake at breakfast.

Anonymous

my gyn recommended flaxseed years ago prior to my bc diagnosis (I never did get around to trying it); but said no once I was diagnosed. Apparently the soy is good before, but not so good afterwards.

anne

rosyFL

Anne, did your gyn say why no flaxseed after your LCIS diagnosis?    I know that soy is out, but what was the reason given for no flaxseed?    I feel like I need to do something.  Cannot take tamox or evista due to COPD.  I had decided after my first oncologist visit that I would opt out of the drugs.  They really push the drugs and most won't discuss other things we can take or do that may also help us. 

When I got to Florida from NYC, I had to find a new oncologist, and he was the only one of three that said no tamox or drugs for me because of my lung disease.  And I'm still confused about this diagnosis, is it or isn't it cancer?  Some say it is and some say it isn't.  Lots of different opinions about LCIS.

Rosy

Anonymous

rosy---because flaxseed is a phytoestrogen, much like soy.  I was taking tamoxifen  to block the estrogen (from reaching receptors in the breast tissue), so it would be defeating the purpose if I took more estrogen in my diet (by way of flaxseed).

Technically and pathologically, LCIS fits the definition of an in-situ breast cancer; there are cancerous cells contained in the breast lobules that have not broken thru to the surrounding breast tissue. so while it IS a non-invasive bc, it is not viewed as a "true cancer" by most, as it  is not invasive in nature. So it is thought to be more of a marker for higher risk of invasive cancer in the future.

I have had several COPD patients that take evista, as it is an osteoporosis medication (and many people with COPD have osteoporosis due to the steroids they take), so I'm not quite sure why your doctor said no to evista (perhaps there are other reasons besides your COPD?)

Anne

rosyFL

No other health reasons that I know of besides the COPD.  I didn't know that flaxseed was like soy, so I guess I won't be eating that anymore.  So what's left for me?   I've been drinking a green drink, cruciferous vegetables (it has no soy in it), so I guess I'll have to just drink the drink and hope for the best.  Boy, this really stinks. 

MsVeryDenseBreasts

FYI, on this topic, in case you ladies have not yet seen this….NCI has a clinical trial posted taking place at U of Chicago and Roswell Park Cancer Center in Buffalo to study the effect of flaxseed (if any) on high risk women.  Both of these are prestigious centers so it would appear that there is a constituencies that at a minimum thinks there is a hypothesis worth exploring.  This study has been ongoing since '08 and is targeted for completion by 2/14.  The purpose of the trial is to determine if flax seed can reduce risk.  Looks like the sample of participants is pretty small. 

http://www.cancer.gov/clinicaltrials/search/view?cdrid=617894&version=HealthProfessional

In addition to some of the digestive benefits some posters have noted, it's also been observed that flax seed can lessen some of the unpleasant side effects of menopause (sweats, hot flashes, helps increase your metabolism etc).  Everyone is different, but I have noticed benefits in this regard. 

MelissaDallas

I go to an NCI Cancer Center and my MO says it is fine and a serving a day of soy (not the protein isolate) is fine too.

Beesie

Flaxseed and soy are both phytoestrogens, but they metabolize differently.  As a result, it appears that while there are questions about the benefit or risk from soy, most studies on flaxseed appear to either show a benefit or no impact at all.  

The following study compared the effects of soy and flaxseed, and concluded that flaxseed causes a shift to less biologically active estrogens, which may have health benefits.

Supplementation with flaxseed alters estrogen metabolism in postmenopausal women to a greater extent than does supplementation with an equal amount of soy

"Supplementation with flaxseed modifies urinary estrogen metabolite
excretion to a greater extent than does supplementation
with an equal amount of soy. This modification by
flaxseed is associated with an increase in urinary lignan excretion.
Despite
the shift in estrogen metabolism to favor the less
biologically active estrogens, a negative effect on bone cell metabolism
was not observed."

"Both the soy and the flaxseed groups
had significantly higher urinary phytoestrogen
excretion than did the placebo group. Although the flaxseed group tended
to
have higher total urinary phytoestrogen
excretion than did the soy group, the difference was not significant.
However, the
flaxseed group excreted primarily enterodiol and
enterolactone, whereas the soy group excreted primarily genistein,
daidzein,
and equol."

"The ability of phytoestrogens (in the present study, those from flaxseed
most notably) to modify estrogen metabolism suggests
a mechanism through which these compounds may be
involved in both disease prevention and treatment strategies. However,
flaxseed
is also a very rich source of α-linolenic acid
(ALA). Flaxseed oil has been shown to reduce mammary tumor growth, and ALA has been shown to alter the growth of breast cancer cell lines in vitro.
Although the mechanism involving the effect of ALA, which may include
an effect on estrogen metabolism, remains controversial,
ALA should not be ruled out as a contributor to the
effects seen with dietary flaxseed."

This small muffin study (small study, not small muffins) found that flaxseed "has the potential to reduce tumor growth in patients with breast cancer."   

Dietary Flaxseed Alters Tumor Biological Markers in Postmenopausal Breast Cancer

And here's what breastcancer.org has to say about flaxseed:

Flaxseed

"Just like omega-3 fatty acids,
flaxseed is a good source of lignans — compounds that may have a weak
estrogen effect. When a weak estrogen-like substance takes the place of
your body's natural strong estrogen in a breast cell's estrogen
receptor, then the weak substance can act as a relative anti-estrogen.
By acting in this way, lignans might help work against breast cancer
that depends on estrogen for its growth. The lignans are concentrated in
the hull of the flaxseed. If the seeds are ground up, your body has an
easier time getting to the lignans."

carol57

Thanks to all of you for this discussion. I asked my onc about this a while ago and was told simply that flaxseed is not harmful, but without any explanation for why. Information you've shared here fills in a lot of blanks.

georgie1112

My naturopath who teaches at a Naturopathy College recommends 4 TBL of ground flaxseed to prevent bc. She only recommends supplements or food based on studies. Sorry I don't know more specifics but this seems to be a good supplement for me without side effects. 

Beesie

I found this 2013 study:

Consumption of flaxseed, a rich source of lignans, is associated with reduced breast cancer risk.

RESULTS:

Flaxseed or flax bread was consumed at least weekly
by 21 % of control women. None of the 19 variables assessed were
identified as confounders of the associations between flaxseed or flax
bread and breast cancer risk. Consumption of flaxseed was associated
with a significant reduction in breast cancer risk (odds ratio (OR) =
0.82, 95 % confidence interval (CI) 0.69-0.97), as was consumption of
flax bread (OR = 0.77, 95 % CI 0.67-0.89).

CONCLUSIONS:

This
Canadian study is, to our knowledge, the first to report on the
association between flaxseed alone and breast cancer risk and has found
that flaxseed intake is associated with a reduction in breast cancer
risk. As dietary intake of flaxseed is modifiable, this finding may be
of public health importance with respect to breast cancer prevention.

And this from 2012:

Flaxseed sprouts induce apoptosis and inhibit growth in MCF-7 and MDA-MB-231 human breast cancer cells.

Flaxseeds have been shown to play a role in the prevention of cancer and
heart disease, and it is believed that their more favorable fatty acid
composition is responsible. Sprouting is a natural method to modify
nutritional components and to decrease cyanide poisoning of raw
flaxseeds. Here, we investigated the in vitro effects of flaxseed
sprouts on cell growth and apoptosis of human breast cancer cells. In a
series of in vitro experiments, estrogen-receptor-positive (MCF-7) and
estrogen-receptor-negative (MDA-MB-231) cells were cultured and treated
with flaxseed sprouts, and then cell proliferation, apoptosis, and gene
expression were measured. Flaxseed sprouts significantly reduced the
growth of both of MCF-7 and MDA-MB-231 cells and also increased
apoptosis. However, flaxseed sprouts did not affect the growth of
MCF-10A mammary epithelial cells. In gene transcription analysis using
quantitative real-time polymerase chain reaction, flaxseed sprout
treatment significantly upregulated p53 mRNA in both cell cancer lines.
These results suggest that flaxseed sprouts induce apoptosis and inhibit
cancer cell growth, thereby demonstrating their anti-proliferative
effects in breast cancer cells. This study may provide important
information for devising dietary strategies to reduce breast cancer
risk.

I used to consume more flaxseed that I do now.  I just sort of drifted away from using it.  think I start adding it back into my diet.

MelissaDallas

thanks for posting ths Beesie.

Beesie

You're welcome.  It's been interesting to me that the results on soy and flaxseed seem to be quite different.  I've always been interested in the flaxseed studies because those first muffin studies were done at my hospital right at the time when I was being treated, but unfortunately I never was offered the opportunity to get in on the study. I tried to continue to follow-up on the flaxseed studies since then although there don't seem to be too many of them.

flannelette

I've got 2 books by Drs Richard Beliveau and Denis Gringras, cancer researchers at the University of Quebec at Montreal. They investigate many plans , herbs, spices - this little quote is from their section on flaxseed "Lignans are compounds present in many plants, although flaxseeed is by far the best source of these dietary molecules. Flaxseed contains very high levels of secoisolariciresinol and its close relative matairresinol. These compounds are important in the prevention of cancers whoae growth depends on estrogens, because intestinal bacteria are able to convert them into enterolactone and enterodiol, two molecules that interfere with the bonding of estrogens to breast cells." ....contrasting with soy isoflovane supplements which promote them....

Also, there's the antinflammatory effect from flaxseed's very high omega 3 fat.....

My former gp recommended these books, full of great info on research on foods - you may have seen them, Beesie, being Canadian

flannelette

ps wasn't that flaxseed muffin study done at U of T?

rosyFL

I am happy to see that ground flaxseed is a good thing for us and that this topic is still of interest.  Does anyone have any information on how much to use on a daily basis?   I'm sorry if I missed anyones recommendations on amount to take.

georgie1112 wrote 4 tbs. a day.  How do you take it?

 Thank you everyone who contributed to this topic.

rosy

Beesie

flannelette, sorry I missed your post with your question.  Yes, the study was done at U of T and PMH. 

rosy, the muffin study used muffins with 25g of flaxseed.  That's just over 1 and a half tablespoons.  When I use flaxseed (I'm still not back in the habit of using it daily) I tend to sprinkle one or two tablespoons over whatever it is I'm eating, usually either salad or yoghurt.

MelissaDallas

I've even used ground flax mixed with almond meal to make crusts for low carb pies.

ballet12

In the study cited above they say that flaxseed sprouts are safer than raw flaxseeds: "to decrease cyanide poisoning of raw flaxseeds." That's a scary thought.  I use raw flaxseeds that are ground during the making of a smoothie.  I wonder about the cyanide issue.  Time to do more research.  Just when using flaxseeds sounded like a good idea.

Beesie

Ah, what's a little cyanide? 

MelissaDallas

Beesie, but cyanide's all NATURAL. Must be good, no?

Anonymous

Hello, ladies. Thanks so much for all the helpful research and comments. After reading all of it, I purchased a six-pound jug of flaxseed and a grinder and began eating copious quantities hoping not only to keep any leftover cancer cells from growing, but to help lower my sudden high cholesterol (compliments of the Letrozole I’m taking). I was feeling really good about it until I read one of the studies Beesie posted a little more carefully. Just one little line in the study, but I found it somewhat alarming, as it seems to suggest that in the absence of estrogen (such as we’d have with aromatase inhibitors), the lignans in flaxseed stimulate the growth of cancer cells. Yikes! It’s in the study called “Dietary Flaxseed Alters Tumor Biological Markers in Postmenopausal Breast Cancer.” Look under Figure 1 in the sentence beginning “In vitro…” “In vitro studies have shown that lignans…stimulate growth of estrogen-dependent human breast cancer cells in the absence of estrogen and inhibit growth in the presence of estrogen.” That seems pretty straightforward, and I can’t think of any other way to interpret it except that taking the flaxseed with any aromatase inhibitor might not be wise. Not to mention the cyanide poisoning thing…

Geez…it is so hard to know if you’re doing the right thing! For now, I guess I’ll regretfully lay off the flaxseed. But I’d be interested in hearing how y’all would interpret that line.

Beth

TB90

I purchased ground flaxseed today despite knowing that it loses its effectiveness quickly.  Does anyone know how long ground flaxseed is good for and I will be watching for other comments also.  Perhaps it was too good to be true??

leaf

I'm no expert, but I do trust Nutrition Diva: she is a registered nutritionist, often uses Pubmed references, and prefers to make choices based on science.

http://www.quickanddirtytips.com/health-fitness/he...

http://www.quickanddirtytips.com/health-fitness/he...

She doesn't mention flax seeds in this question about breast cancer

http://www.quickanddirtytips.com/health-fitness/pr...

If
you are buying pre-ground flax, buy only small amounts that you can use
up in a couple of weeks. This is not the time to buy the 100-pound sack
from Costco. Also, look for packaging that protects the ground seeds
from light and air and check your expiration dates. Finally, store
ground flax and flax oil in the refrigerator, not in the cupboard. Any
flax product that has a rancid or fishy smell should be discarded. - See
more at:
http://www.quickanddirtytips.com/health-fitness/healthy-eating/flax-facts#sthash.NHsavaOb.dpuf

Anonymous

I wanted to make it clear that in my comment above, I was only questioning the use of flaxseed for those of us taking an aromatase inhibitor.  And that was based solely on the one line in the flaxseed study that seems to suggest that in the absence of estrogen, the lignans in flaxseed stimulated the growth of estrogen-dependent human breast cancer cells.  Supposedly, aromatase inhibitors produce something pretty close to an absence of estrogen, so I could only conclude that it might be unwise to take the flaxseed if you're taking an aromatase inhibitor.

Ah, sometimes I think I'm wasting my time with all this research since it so often leads me right back to where I started.  I really feel out of my element anyway.  I don't have any medical background----I don't even have a college degree----so I'm not even sure I'm interpreting what I read correctly.  Which is why I asked how y'all would interpret that line.  My oncologist shows no interest in anything alternative.  I feel like a pig in a chute at this clinic anyway---it's "Here's your letrozole prescription.  Keep taking it and if you can't, you can try the other two---see you in three months!"  I always feel discouraged when I leave.   

flannelette

blueridge - well, that was pretty astute of you to read the study so closely - and thanks, I WAS taking arimidex, am now finished my 5 yrs, was going to jump on the flaxseed wagon.......but maybe just a little, now..maybe will take Indole 3 carbinaol instead - but who knows every little thing about THAT? just like when I started taking soy isoflavone years ago to prevent hot flashes during menopause, now I think I was aiding the cancer cells to start up a colony. oh yes, rubbing natural progesterone cream on my breasts, too, aafter reading Dr. Lee. No, I got no hot flashes, not one, just got Er+ Pr+ br ca instead. Hm. Alittle knowlefge can be a dangerous thing. We borrow from other cultures who have less of a certain type of cancer than we have. but what they do, unlike us, is have an overall diet and start youg - food IS their medicine. We just take the parts we thing are right. WRONG!

best to store ground flaxseed in freezer rather than fridge. it's probably genetically modified and treated with pesticies, anyway..............

Anonymous

Thanks so much for responding, Flannelette.  And congratulations on finishing your five years of Arimidex!  

It really is so hard to know what the right thing to do is.  "Do this!" changes to "Don't do this!" in the blink of an eye, it seems.  It would be nice if oncologists took a little more interest in helping you figure out how to integrate the conventional treatments with the alternative ones instead of just pushing pills.  I'd like to feel like I have a partner in my treatment plan, but I feel very much on my own.  

TB90

Flannellette:  All I can say is sh_t!  Every time I try to do something correct, there are so many factors dismissing or even opposing it.  It is so very confusing and frustrating. I think I will just throw it out and eat my veggies.