Not eating dairy / soya for Hormone ++++

Hi fellow pinkies,

Does anyone know why its been suggested for people who have had BC to not have any dairy / soya products, especially if you are hormone positives??

Any advice would be very welcome!


Sarah X

I think soya is a plant oestrogen so thats why er+ people should avoid it. Although i think some say the opposite.

As far as dairy goes, i had my ovaries removed aged 35 as i was 100% hormone positive and therefore have been told to eat extra dairy to protect my bones!

It is to do with IGF-1 (insulin growth factor found in meat, dairy and soya). I’ll try and post a research article on this tomorrow.

There is no evidence whatsoever that excluding dairy from your diet has any affect on breast cancer - although people like Professor Jane Plant (professor of Geology) would have you believe otherwise.

Plenty of vegans get BC - myself included.

The jury is very much out on soya - although soya derivatives such as genisten supplements have been found to interfere with Tamoxifen.
Eat well, keep within a healthy BMI (fat DOES have a significant role to play in BC), keep booze to a minimum and treat most claims about dietary involvement with healthy scepticism.

NB - in the EU growth hormone in cattle is banned. A lot of stuff on the internet makes claims about this association with cancer but they are usually US sites and it does not apply to us.

Msmolly…that is the most sense I have seen in a long time!

I produce all my own meat and have done so for 30 years, and as a result eat it with respect and infrequency as its a valuable bit of home produce. I also produse lots of my own veg and for 20 years produced my own goats milk. (I also used to milk commercial dairy cows for about 15 years) My OH is a vegetarian and we have mutual respect.

The nonsense I read about meat and dairy is usually all based on non EU films/reports/statistics etc and we actually have the highest welfare and food standards in the world here as far as I am concerned and our food is safe.

Lots of people of all ages, races and lifestyles get BC…it does not discriminate and I know veggies and vegans who have been affected by it.

The most important thing is a healthy diet, a healthy lifestyle and a healthy BMI!!!

There is a significant amount of research on the relationship between insulin, Insulin Like Growth Factor and cancer. There is a strong correlation between high serum levels of insulin and IGF and cancer risk, and those with the lowest levels of IGF have a cancer risk approx 30% lower than those with the highest levels. It is known that the diet resulting in the lowest levels of IGF is one that excludes dairy, meat and soya milk (not other soya products). There is evidence that excluding dairy and meat affects progression of prostate cancer, but no comparable research has been undertaken (ie an intervention study)with breast cancer patients.


Diet is and always will be a contraversial subject and imho to cut out dairy especially is to risk osteoporosis in an omnivore such as I and the fact that I have a high risk family for bc is more impt to me than my very healthy diet…which contains very little processed food…we even make our own bread.

I am not going to worry myself half to death over this and would encourage others not to either…

Osteoporosis is of course a risk and something that we need to be careful about, but there are many non-dairy sources of calcium for those that do want to consider cutting down or excluding dairy.

finty x

Hi Sarah,
There are a lot of myths and theories banded about re Dairy/meat/sugar ect and breast cancer, but as yet there is no proven scientific evidence to suggest avoiding these foods.
Infact most of the reputable and largest studies to date continue to find no strong link between Diet and BC .
Its a subject that is often debated on the BCC forums, if you do a search or look in the archives it may be of some
help to you as it can often be a confusing subject,
The current advice is to eat a "healthy balanced diet,"avoid/limit alcohol,and to avoid obesity.
Regarding Soya a lot of oncologists advise against it because of its very high amounts of Phytoestrogens.

All the best to you

On the contrary there is quite a lot of evidence suggesting avoiding these foods is beneficial if you have hormone positive breast cancer. This article from the Journal of Endocrinology explains the connection between IGFs and breast cancer:

Specifically interesting is this conclusion:

" … once IGF interacts with receptors, IRS is the predominant signalling molecule activated in oestrogen positive breast cancer cells. IGF influences breast cancer cells responsiveness to oestrogen."

The diet lowest in IGFs is one that is low in the amino acids present in animal protein - specifically dairy and meat. A diet excluding dairy and meat is also much higher (40%) in the binding proteins that lock up and neutralise circulating IGFs.


I had an email from Tim Key (EPIC) a few weeks ago which may be of some help to those ladies who are worried or confused about the Diet and BC issue ,i posted it on the Red Meat thread at the time ,so apoligies if some of you have already seen it, Ive copied it below.


I recieved a lovely email today from Tim Key ( EPIC Study ) i thought some of the ladies here might find it interesting so ive posted it below to give us some answers on diet and BC from the largest ever study (well Massive actualy) ever conducted to date .

Professor Tim Key,
Deputy Director, Cancer Epidemiology Unit,
University of Oxford, Richard Doll Building,
Roosevelt Drive, Oxford OX3 7LF
<script type=“text/javascript”>eval(unescape(‘%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%54%69%6d%2e%4b%65%79%40%63%65%75%2e%6f%78%2e%61%63%2e%75%6b%22%3e%54%69%6d%2e%4b%65%79%40%63%65%75%2e%6f%78%2e%61%63%2e%75%6b%3c%2f%61%3e%27%29%3b’))</script>

Hi Linda
Thank you for your email.I am sorry for the delay in replying,I was away last week.
I have tried to answer your questions - see below.

  1. Has EPIC found a “vegan” (not vegatarian) diet to be better for fighting/preventing breast cancer .

  2. Has Dairy/Red meat/Eggs/Sugar been found to be
    cancer contributeing/causeing in breast cancer.

The answer is the same for both these questions. The only dietary factors that definitely increase the risk of breast cancer are obesity and alcohol.

No other aspect of diet such as vegetarianism, meat, dairy,
sugar etc. has been definitely shown to affect the risk for developing breast cancer.
However, research on this is continuing and it may be
that some links will be found in the future. In relation to vegan diets there is simply not enough information
anywhere in the world to draw any conclusions.

In relation to fighting breast cancer, the only strong evidence in relation to diet is that obesity has been
associated with a higher risk of the disease progressing.

  1. Re IGF1 levels , have higher levels of IGF1 proved to cause breast cancer.

There is now a substantial amount of evidence suggesting that women with relatively high blood concentrations
of IGF-I do have a moderately higher risk for developing
breast cancer compared to women with relatively low IGF-I.
It seems likely therefore that IGF-I does play a role in
increasing risk. However, more research is needed to clarify the importance of IGF-I.

  1. Is the hormones in Cows Milk a factor in causeing breast cancer

This is not known.

  1. Can useing suppliements help in breast cancer fighting/prevention.

No, not as far as we know at present.

6.Some also believe that “the intensive diet lifestyle change prostrate study” ,is proof that a vegan diet
does prevent cancer progression.

This research area is interesting but there is not yet enough known to draw any firm conclusions,
therefore there is not any proof that a vegan
diet does prevent cancer progression.

I hope that these answers are helpful - there is still a lot that we don’t know. Some of our research here
is following the possibility that dairy products might perhaps increase risk by increasing IGF-I, but we
don’t know yet if there is much truth in this hypothesis.
Therefore the best dietary advice we can give is to choose
a conventional “healthy diet”, to avoid obesity,
and to limit alcohol consumption.

With best wishes

Tim Key

Thanks for this indepth info ladies…

As I very rarely drink and have a BMI of 20.5 had my babies young, breast feed for 1year both times, eat a healthy diet and ran 14 miles a week, it seems i shouldn’t have even had BC in the first case!!!

Sarah X

Hello Ladies, there is so much conflicting information and opinions it makes your head spin ! I myself have given up dairy /red meat as I am er+ and have secondaries. I am generally eating much more healthily and dont feel so bloated and I have lost a few pounds (so thats gotta be a good start). The statistic that made me give it a try is this : the chinese eat a dairy free diet - although statistics are increasing slightly as China becomes more westernised only 1 in 100,000 women die from bc - in the western world its as much as 1 in 10 - of course there may be other reasons for this massive difference but for me, its worth a try - I will continue to read as much as I can on the subject as I do feel what we eat is so important but I reckon we dont know the half of it and the only way to be sure we are not poisoning ourselves is to only drink water from a natural spring and eat food we have grown/reared ourselves and that aint gonna happen anytime soon ! Hey Ho ! Onwards and upwards x Debbie x

Thanks Finty for posting the research I didn’t have time yesterday.

I suppose the question is what to do with all the information.

I do still eat meat but keep the amount I eat low and for the most part organic chicken. Becuase of the IGF levels found in vegan women who have soya I have also eliminated that. I have eliminated dairy as well. It boils down to personal choice, and whether you feel that the potential high IGF-1 levels have for increasing cancer risk is worth making a change to dietary lifestyle or whether you want to wait for further research clarification.

Sarah, you mentioned alcohol. Research shows that does increase risk particularly in ER+ women and particularly although not exclusively in those with lobular cancer. As I am ER+ and had lobular cancer, I have eliminated alcohol except for the very occasional drink - I’ve had 5 weak alcoholic drinks in the past 12 months.
Again for some people, this impacts too much on their quality of life for them to make the change.

I sound a bit saintly but I’m overweight and haven’t been able to cut back on sugar and dark chocolate and generally eating too much. I know weight is an issue and I will be working on that this year!

Debbie, I agree - having secondaries focusses the mind in ways that those with primaries will find difficult to understand. There will never be definitive proof in our lifetimes, so those that are waiting for scientists to prove the connection to them beyond all doubt will wait in vain. But that does not mean that significant evidence does not exist - it does, but it requires analytical skills to connect the dots, and that is difficult for laymen, but it doesn’t mean we shouldn’t try. Diet is too complex an issue to isolate individual variables, so statements such as Tim Key’s on the EPIC trial are exactly what any ethical scientist will tell you - there is no definite proof and not enough information to draw definitive conclusions - emphasis always on “definitive”. And observational trials like the EPIC survey have a limited value in that they are simply not testing the hypothesis that we are discussing - I don’t know why anyone expects a research project to answer a question it wasn’t asking - it’s just bizarre. And because one project doesn’t answer a question, it’s an odd logical fallacy to then dismiss all other research on the subject as of no value. We have to look elsewhere for the answers, and there is plenty of research that all points in the same direction. The correlation between IGFs and cancer has been established, and there is solid science that indicates causation.

Observational studies such as EPIC are acknowledged to be seriously flawed (see Ben Goldacre, Bad Science) and interventional studies are far superior, but far more difficult to recruit to and run. The ONLY interventional study we know that has looked at this issue in live cancer patients showed that a near-vegan diet enabled a group of men with active cancer to keep their cancer from progressing (and mostly it regressed) compared to a control group on a “normal” diet. That is simply amazing, and enough I would have thought for most people with cancer to consider a change of diet. It involves no drugs, no nasty side effects (on the contrary it will make you feel better and you will lose weight), no additional cost (it’s actually cheaper) - simply eat a healthy diet excluding some foods and you might live longer. Tim Key acknowledges this with the obvious caveat that we can’t draw any firm conclusions from it. Well, if I were a scientist publishing my results I would be ethically bound to use such circumspect language, but I’m not - I am someone with cancer that can’t wait another 50 years for long term studies to prove what seems to be a clear picture emerging from many different angles of approach.

The correlation between IGFs and cancer exists, and the correlation between IGFs and consuming animal protein exists. These are facts that simply cannot be disputed by any reasonable reading of the data. I am happy to gamble on going one stage further and assuming causation, so have altered my diet accordingly. The evidence is not that dissimilar to the evidence on smoking, alcohol, obesity and breast cancer. The correlation is firmly established, and various pathways for the causation have been mooted - but as far as I am aware none have been established by an interventional study with a control group in the way that diet has in the prostate study. But we are happy to accept these risk factors because the correlation is strong and these are single variables that are easy to isolate, where diet is not. There is an odd double standard here of accepting certain evidence on purely correlation, but not other equally valid evidence that relates to diet.

finty x

Hi elinda45

Was interested in your last post…I have invasive lobular cancer, ER+ and have always drunk quite a lot of alcohol.
I would find it difficult to give up completely as I enjoy a glass of wine with food and a lot of my social life involves alcohol but I have cut down (I’m mid chemo and often my body just does not want alcohol)
I’d be really interested of you could point me in the direction of research linking alcohol and ER+ lobular cancer as it could be just the push I need to further reduce my intake and I’d like to be informed about exactly what I’m doing to myself booze-wise

Hi Suzy

Try this website - it has diet research categorised by type of breast cancer, and there is a section on lobular:

I do sympathise - I have always enjoyed wine, and drunk probably more than was healthy. But I have cut down to a very minimal amount - maybe 2 or 3 glasses of red wine a week, and haven’t found it that hard most of the time. Parties are difficult - but then I was finding the drink was exacerbating hot flushes in crowded situations anyway, so perhaps just as well.

finty x

Here’s the link for the lobular section:

finty x

Thanks finty, will read those now

Really interesting…and sobering reading.

Have taken note and know I need to cut down on the booze and also my sugar intake is too high…also love a bacon butty! On the other hand I’ve always tried to eat a lot of fruit and veg, just seems to make sense so I’ll increase that even more. I won’t be giving anything up completely as I’m far too weak willed but will avoid more stuff now. Thanks for those links, appreciated