Soy or Not?

ausykaren
ausykaren Member Posts: 64

Can someone please clear up whether women who have hormone positive breast cancer can have soy milk or not? Studies on this subject are very conflicting. I asked my oncologist and she said it’s ok to have. I’m so confused.


Comments

  • sunshine99
    sunshine99 Member Posts: 2,723
    edited February 2021

    Ausykaren, I agree that the "evidence" is very conflicting. Soy is good - soy is bad. Coffee is good - coffee is bad. The list goes on and on. I'm not a doctor (and I don't play one on TV), but it seems that moderation is the key for just about everything.

    I do believe that stressing about what we put in our bodies is more harmful than what we actually eat or drink - within reason, of course.

    Carol

  • exbrnxgrl
    exbrnxgrl Member Posts: 5,316
    edited February 2021

    sunshine,

    I couldn’t agree more, especially with your last sentence. When I was first diagnosed I worried about every bite that I put in my mouth, followed a restrictive diet, etc. Not only was I stressed and grumpy but I was fighting with my younger dd who had taken on the roll of food monitor. I am not suggesting that folks live on unhealthy foods but I always had a reasonably healthy diet so I went back to it and feel hugely relieved of the burden of thinking that each bite of “bad” food was going to make my bc progress. I can’t say whether or not my approach has worked, in terms of progression, but I am almost at the 10 year mark at stage IV with no progression since initial tx. I do know that I am a million times more relaxed and happy since I let go of food worry and restrictions.

    Several years ago a member posted that she had eaten 10 potato chips. She felt guilty and worried about how this might effect cancer progression. 10 potato chips? I think the stress and worry over having eaten them was potentially more harmful than the chips themselves. For me, that’s no way to live but I do acknowledge that it’s important for some people to be actively doing “something” beyond conventional tx. Again, I’m not advocating for a diet of Twinkies, chocolates and wine with side of fries 🍟 but I don’t think it helps many of us to worry about everything that crosses our lips.

  • mindig66
    mindig66 Member Posts: 41
    edited February 2021

    My MO said soy is fine - in moderation. I asked what moderation was and he said studies indicated 5-7 servings per week.


  • mac5
    mac5 Member Posts: 85
    edited February 2021

    hello ladies

    Back in 2008, I was told to avoid soy at any cost because our bodies use it to produce estrogen. But we also use body fat to produce estrogen. And since I’ve ballooned since taking Ibrance and Letrozole I questioned my DO about whether or not the extra body fat was making my Stage IV worse.

    I’m told that Ibrance and Letrozole prevent the breast cancer cells from using estrogen for growth. That made great sense to me. I’m still not happy with the weight gain, but less concerned that the additional estrogen is going to kill me quicker.

    We all produce estrogen because we can’t survive without it. So foods like soy and carbs are not the enemy I think. Healthy balanced diet I think is the solution.

    But if you feel differently, do whatever makes you feel like you’re fighting

  • minustwo
    minustwo Member Posts: 13,393
    edited February 2021

    Moderation has been my watchword, as the first two posters suggested. And that includes everything in my life, from soy to exercise to alcohol.

    I will say that I am ER/PR negative - and I think the recommendations are different. You've posted this in a HER2+ positive thread but your sig line says you are HER2 negative. BUT you are ER/PR positive. What did your docs say given your particular cancer?

  • melissadallas
    melissadallas Member Posts: 929
    edited February 2021

    My NCI docs said a serving or two a day is fine. Preferably natural forms and not the modified stuff like they put in protein bars

  • ausykaren
    ausykaren Member Posts: 64
    edited February 2021

    Hi MinusTwo, I posted this question in the general stage 3 forum and for some reason the Moderators moved it to a Her2+ thread. Saying I will get more replies. I don’t think so! My oncologist just said yes to soy without any explanation but if I told her that I saw conflicting studies on the internet, she would tell me to get off the internet as she has before lol



  • minustwo
    minustwo Member Posts: 13,393
    edited February 2021

    Ausy - And in some ways I think your doc is correct - good old "Dr. Google" has no medical degree & can be very misleading.. But I do think you could research at reputable medical center sites - like Mayo Clinic or Johns Hopkins or MD Anderson. For example - below is a link to several answers from Mayo

    https://www.mayoclinic.org/search/search-results?q...


  • kathabus
    kathabus Member Posts: 45
    edited February 2021

    To expand on what Melissa said above....my oncologist suggested to stay away from “soy protein isolate.” It’s in a lot of protein packed bars and shakes. But it will pop up in random things....likefrozen meatballs 🤷🏼♀️

  • ausykaren
    ausykaren Member Posts: 64
    edited February 2021

    Thanks MinusTwo and everyone else for posting.


  • stephincanada
    stephincanada Member Posts: 29
    edited February 2021

    I have started eating fermented soy beans (called "natto") for its health benefits. But, I noticed it had an estrogenic effect (I sleep better, my boobs got bigger, joints hurt less, etc.) So, I've cut way back on the amount I eat. I would see if eating soy causes any body changes and go from there...

  • jinnynh
    jinnynh Member Posts: 26

    I agree that the articles published on the Internet are confusing, to say the least. Some say no so at all, others only fermented soy (which excludes tofu), and still others say several servings of tofu a week are fine! I don't know whether to trust the official sites (FDA, for instance) because they're not always that objective; sometimes they seem to be "pushing" certain substances that are subsequently deemed as harmful. So who to believe? Having gone on a mostly plant-based diet, I am sometimes puzzled about whether or not to avoid soy. Very frustrating when you're caught in the middle of what seems to be an ideological argument!

  • moderators
    moderators Posts: 8,740

    Hi all,

    You may find this recent Research News article interesting:

  • cure-ious
    cure-ious Member Posts: 2,926

    Soy in drinks is always fine, its just soy supplements that bring in high levels that one might worry about- the concern is that the phytoestrogens in soy (these are plant estrogens that work in human cells but are much weaker than human estrogen) could stimulate growth of breast cancer in those on endocrine therapy, where the body has been turned into an estrogen "desert" and even weak plant phytoestrogen signaling is stronger than nothing. But even at that, there are not clear data showing that soy supplements are actually dangerous

    For those who do not have MBC and are just trying to prevent recurrence of their cancer, or prevent a primary tumor, soy supplementation is a good idea, because the plant phytoestrogens in the soy will compete with normal estrogen for binding to the ER, and when they do bind they are much less effective in stimulating ER activity, so the net effect is that soy dampens ER signaling when added to cells that have normal or high estrogen levels..