I’ve been getting an increasing amount of questions about whether collagen supplements are safe for breast cancer survivors, and indeed, I’ve run across a few articles lately warning us about collagen supplementation. So today’s article is dedicated to shedding some light on the subject, and hopefully answering that question.
If you’ve noticed, there are a number of companies promoting collagen supplements at the moment. They are promoting it hard – like a new wonder drug – for better skin and nails, better hair (which I suspect is the reason people are asking me about collagen, to help them with hair loss due to breast cancer treatments), better gut health, for weight loss, and for its so-called anti-aging benefits.
But is it safe for breast cancer survivors? At first glance, one would think, well why not? If it’s already in our bodies, why wouldn’t it be safe?
Let’s look a little deeper into this.
The Role of Collagen
Collagen is a long chain of proteins and sugars (known as a glycoprotein), and is the most abundant protein within our bodies. Collagen is found in skin, hair, cartilage, and many other tissues, and it is absolutely vital. Collagen is also the major component of something called the extracellular matrix, or ECM.
The ECM is a network of molecules such as collagen, enzymes, fibers, proteins and glycoproteins that exist outside of our cells – sort of like a scaffold, in order to support the cells with which they are associated. The ECM provides structural and biochemical support to the cells surrounding the ECM and there is an interaction between cells and the ECM – it helps to inform cells about growth and many other functions. 
The interaction between cells and the ECM provides for things like regulation of gene expression, cell differentiation and growth. So far so good. But this interaction between the ECM and cells can also play an important role in the growth of a tumor and its ability to grow and spread.
According to Sara Musetti, scientist and co-founder of OncoBites, a cancer research outreach blog, cancer takes all the good things about collagen and turns them into a nightmare. Musetti tells us “Collagen is used to support and protect, so naturally tumors twist it to their advantage. Tumors are often full of fibroblasts, the major cell type responsible for producing collagen. These cells pump out huge amounts of collagen, swaddling little pockets of tumor cells, called tumor nests, in blankets of collagen that keep damaging agents away. These collagen-rich regions form a physical barrier around tumor cells that keep chemotherapeutics, immune cells, antibodies, and other therapies from reaching the cells to kill them. The particular shape and character of collagen in a tumor has even been linked to how easily the tumor grows and spreads.” 
I found that fascinating – this ability of collagen to hide tumor cells in protective pockets so that immune cells and chemo drugs can’t get to them.
A 2013 study  found that DDR2, a protein that sits on the surface of tumor cells and binds to collagen, activates a pathway that encourages the spread and invasiveness of tumor cells. Researchers stated that DDR2 might very well be a good therapeutic target for treating metastasized breast cancer.
A 2014 paper  in Tumour Biology stated “While collagen was traditionally regarded as a passive barrier to resist tumor cells, it is now evident that collagen is also actively involved in promoting tumor progression. Collagen changes in tumor microenvironment release biomechanical signals, which are sensed by both tumor cells and stromal cells, trigger a cascade of biological events. In this work, we discuss how collagen can be a double-edged sword in tumor progression, both inhibiting and promoting tumor progression at different stages of cancer development.”
Another 2014 paper  stated that both hyaluronan (another glycoprotein found in the ECM) and collagen VI are upregulated (promoted) in breast cancer, generating a microenvironment that promotes the progression of a tumor and also metastasis.
In her 2015 YouTube video “Understanding the Role of Collagen in Breast Cancer” , Dr Patricia Kelly explains that breast cancer cells use the collagen network in order to travel to other parts of the body.
A 2016 article in Science Signaling  stated that TM4SF1 (a protein encoded by the gene TM4SF1) promoted the reactivation of dormant breast cancer cells in the lung, bone, and brain by promoting signaling when cells came into contact with type I collagen. Also, high TM4SF1 expression correlated with reduced metastasis-free survival in breast cancer patients, and that for those who had high expression of TM4SF1, this was highly predictive of their breast cancer recurrence.
Interestingly, it appears that different types of collagen can also suppress tumor growth. A 2015 animal study  found that type III collagen (col3) suppressed the carcinogenic microenvironment of a developing tumor. That was the only study I found that showed a particular type of collagen suppressed tumor growth.
A 2018 study  found that type 1 collagen promoted breast cancer cell growth and the ability to migrate to distant parts of the body.
Another 2018 study  also showed that collagen type 1A1 promoted breast cancer metastasis.
A 2018 article published in Breast Cancer Research  stated “Increased collagen expression and deposition are associated with cancer progression and poor prognosis in breast cancer patients.” The focus of the study was on a type of collagen known as collagen XIII. It was found that expression of this form of collagen was significantly higher in human breast cancer tissue compared with normal, healthy breast tissue, and that increased collagen XIII levels in breast cancer tissue correlated with increased tumor recurrence, promoted invasive tumor growth and enhanced breast cancer cells.
A 2019 review of medical studies on collagen  called collagen a “double-edged sword” with regard to cancer. The review reiterated the fact that our bodies have lots of collagen and require it for proper functioning. However, collagen is the major component of the tumor microenvironment and has been shown to participate in cancer development. Cancer cells use and reshape collagen, utilizing it to improve invasiveness, increase the ability of cancer cells to resist dying off, for building new blood vessels (angiogenesis), and many other functions, which gradually promotes cancer progression. Also, collagen-rich environments lack oxygen (known as hypoxia), which intensifies cancer progression.
The study at  concluded: “Cells and molecules in the tumor microenvironment have dual effects on cancer progression. The role of collagen is a double-edged sword in cancer. On the one hand, collagen, cancer cells, other cells, and other matrix molecules mutually form an inter-reinforcing loop. This loop contributes to the development of cancer by inducing cancer cells proliferation, migration, and metastasis. On the other hand, preclinical and clinical studies have demonstrated that collagen may slow the development of cancer cells to some extent under some conditions. In summary, the association of collagen with cancer is only partially understood, and future studies are needed to elucidate detailed collagen biological mechanisms in cancer tissue that can be applied to precisely regulate collagen balance to achieve the maximum benefit of treatment. This new strategy combined with other treatment modalities can ultimately improve patient survival and quality of life.”
One Chinese doctor at a burns unit in a Beijing Hospital (who did not wish to be named) clearly held a dim view of collagen supplementation, calling them absolutely useless. He said that after digestion, collagen disintegrates into amino acids, which are also found in the proteins of commonly-consumed foods like eggs, meat and beans. “The best result you can hope for after eating collagen is no effect,” the doctor said. “It would be more dangerous if you found the collagen effective, because then estrogen must have been added to the product.”
The Bottom Line
It is clear that researchers believe that many types of collagen promote tumor growth. Because it has been observed that breast cancer patients with high levels of collagen in their tumors often have less than optimal outcomes, it is advisable to steer clear of collagen supplementation if you have active cancer tumors in your body.
Because we do not have a definitive answer on whether collagen supplementation is safe for those whose tumors are gone, here’s what I would recommend.
Until we understand more about collagen supplementation, I intend to live by this quotation by wise old Benjamin Franklin: “When in doubt, don’t”.
If you are considered to be cancer free and you believe collagen will be of benefit to you, and your doctor agrees with that, proceed with caution. I don’t believe women with dense breasts should supplement with collagen, as high collagen levels are the reason for increased breast density and are related to higher breast cancer risk. 
 Video: Extracellular Matrix: https://www.khanacademy.org/science/biology/structure-of-a-cell/cytoskeleton-junctions-and-extracellular-structures/v/extracellular-matrix
 Article: The Double-Edged Sword of Collagen — https://oncobites.blog/2019/12/06/the-double-edged-sword-of-collagen/
 The collagen receptor discoidin domain receptor 2 stabilizes SNAIL1 to facilitate breast cancer metastasis — https://www.nature.com/articles/ncb2743
 Collagen as a double-edged sword in tumor progression – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3980040/
 Collagen VI and Hyaluronan: The Common Role in Breast Cancer – https://www.hindawi.com/journals/bmri/2014/606458/
 Video: Understanding the Role of Collagen in Breast Cancer – https://youtu.be/uAHpvwv9iqg
 Cancer reactivated by collagen – https://stke.sciencemag.org/content/9/437/ec165
 Type III Collagen Directs Stromal Organization and Limits Metastasis in a Murine Model of Breast Cancer — https://www.sciencedirect.com/science/article/pii/S0002944015001285
 Collagen type 1 promotes survival of human breast cancer cells by overexpressing Kv10.1 potassium and Orai1 calcium channels through DDR1-dependent pathway – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5973854/
 Collagen – col1A1 – Promotes Metastasis of Breast Cancer and is a Potential Therapeutic Target —
 Membrane associated collagen XIII promotes cancer metastasis and enhances anoikis resistance – https://breast-cancer-research.biomedcentral.com/articles/10.1186/s13058-018-1030-y#:~:text=Increased%20collagen%20expression%20and%20deposition,protein%20within%20the%20collagen%20superfamily.
 The role of collagen in cancer: from bench to bedside – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6744664/
 Collagen Matrix Density Drives the Metabolic Shift in Breast Cancer Cells – https://www.sciencedirect.com/science/article/pii/S2352396416304674
Often enough it is the case that when the body produces a substance, it might be good for the body but when used as a supplement it can be detrimental. And with everyones genes being so individual it is hard to decide what the right choice might be. I agree with you Marnie. If in doubt, don’t take it.
Thank you for the article.
Well stated, Gabriele! You are quite welcome, hope it helped you in some small way.
Marnie….WOW!and that’s what my health professional contacts that helped me make my decisions regarding DCIS treatment had to say when they read this. Needless to say, I have stopped taking the collagen. PLease keep us informed if you have any more information on this matter.
Also, would collagen play any kind of role in ulcerative colitis???? A family member bothered severely the last nine months and not able to get under control,even with steroids.
Thanks for helping.
Lovely to hear from you, it’s been awhile! Yes, this information on collagen was surprising to me as well. Re the ulcerative colitis, I’m afraid that’s not within my area of knowledge, so I wouldn’t care to comment. I’d have your family member speak with a naturopath well versed in that disorder. You can probably find a good one online, but let me know if you need help (I’d need their location).
Biosil is it a safe collagen, I have been diagnosed with mestatic breast cancer.
Biosil does not contain collagen – it looks safe to take.
Hi is a plant based collagen in a powder form organic soil based ok for a 10 year survivor ?
Can you send me a link to the product? I’d need to see it in order to advise you further.
I use plant based collagen biosil is it safe for breast cancer
Biosil does not contain collagen – it should be safe for you.
I am assuming this is taking collagen in pill form. What about using shampoos with collagen in them?
Well even though your skin can still absorb some of it, it would most likely be in such a tiny amount, I really don’t think this would be a problem.
Is organic bone broth okay? My understanding is that it contains collagen
I haven’t read anything that would lead me to worry about bone broth — I believe that the collagen in bone broth works more synergistically with the body – please make sure it’s organic, however. Otherwise you could be taking in a whole big load of toxins.
I am a breast cancer survivor, as of 10 years. They are keeping a check on me every six months at this time, as they notice changes at the surgery site (small ductile lump removal). They say the changes can be calcification of the tissue due to aging, but they watch for two years. I am a 72.
Since I am not aware of any cancer presently, I wonder if it is still best not to take the collagen supplement, with this new concern of the medical group.
Thank you in advance for any reply you may have,
Thanks for your message and for your patience while I found time to reply. Here’s my thoughts on the matter. Firstly, calcification of the tissue is generally considered an attempt by the body to heal itself. So it’s actually a good thing. I would still not advise taking the collagen supplement – there are so many other good things out there that help to reduce risk of recurrence and keep our bodies healthy. If you’re not familiar with what those things are, you might want to consider subscribing to my newsletters – all free. You can find out more here: https://marnieclark.com/8-reasons-to-subscribe-to-my-newsletters/ Just click the button Sign Up Here if you’re interested. Hope this helps and I wish you well on your healing journey.
Thank you Marnie! This article couldn’t be more timely. There is a FB page and group that is becoming very popular here in the US which promotes keto, and clean eating. One of the things that is promoted is collagen. I researched it and found similar information that you provide, and when I commented on their page for BC patients to be wary, I was admonished. Your information puts it all in perspective for me.
You are more than welcome. Sorry the FB group scolded you. That’s not cool. I think I’d be backing out of that one! Wishing you all the best in your healing journey.
Would Biotin be bad for me–I have active met cancer (started in breast)
I would not like to say what is and what is not bad for you without knowing a lot more about your particular health condition. I would certainly not recommend biotin alone as one of the supplements you use to help you manage your condition, but as one of many different health-promoting supplements, there is to my knowledge no problem associated with biotin. If you would like my help in formulating a good protocol insofar as your nutrition and supplements are concerned, I’d be more than happy to assist you.
Thank You for this article, and for all the information you pass along.
Your diligence and help is most appreciated.
Be assured that you are making an exemplary contribution to those who need it most.
With sincere gratitude,
Thanks for your kind words, very much appreciated. Wishing you well in your healing journey.
This is a fascinating article, Marnie. Thank you for presenting this information. I think I mentioned to you once that I did try a collagen powder awhile back and found that it caused me to become depressed. I thought how weird but researched it and found that others like me had a similar experience. As a breast cancer survivor I am glad to know that collagen might not have been quite safe for me after all. I decided to become vegan in December, so in order to get enough daily protein I have added a couple of vegan protein powders to my morning vitamin/health shake. I also take a tablespoon of liquid silica in hopes that my hair will stop falling out. So far, no luck with that, but my nails are hard and no longer split.
I found what the un-named Dr. said about supplemental collagen doing nothing for us in a positive way…to be interesting as well…and tend to believe him. Thank you, Marnie for keeping us informed. You are a blessing.
Thanks, Diane, delighted to hear from you again, and I’m glad you found the article helpful. I note we talked about calcium-d-glucarate, but not collagen. Interesting that it had that effect for you – could just be your body’s way of letting you know it wasn’t for you. Just be sure your protein powders are organic and do not contain soy protein isolate (whole organic soy is good for you, but that particular isolate appears to increase BC risk). Otherwise, you should be good to go.
Very interesting information. Thank you so much for sharing this with us. 💜
You are more than welcome, thanks for your comment.
This is such a bummer. I started a collagen creamer back in February and it has helped my skin clear up and my hair grow. Now I guess I’d better stop. 🙁
Oh, I’m sorry! I feel your pain. Sending far away hugs.
I’ve been drinking collagen powder for about three years. In 2019 I felt a lump in my right breast. Turns out it was a 2.5 cm papillary lesion with a Stage 0 carcinoma. I had a mastectomy and thought all was good. At one year followup, a small lump developed near the incision site. I noticed from that point that it was growing bigger. Just had it removed a month ago and they found out another papillary lesion grew back in exact same spot and measured 2.7 cm. Pathology report shows a tiny carcinoma in the mass that was removed. I’m thinking it was the collagen that caused the rapid growth of the lesions. Did research and found info just like you posted in your article. I immediately threw the rest of the collagen in the trash.
Just wondering is it ok to drink bone broth as I believe it contains collagen?
Thanks for sharing that with us. I’m sorry you’ve had such a rough time lately! With regard to your question about bone broth, the amounts of collagen in it vary widely between brands. You might find this article from ConsumerLab.com helpful: https://www.consumerlab.com/answers/how-much-bone-broth-for-benefit/how-much-bone-broth/ As you can see, some products contained 5 times more collagen than others, so if you are committed to consuming bone broth, it would be a good idea to get that information from the maker of your favorite brand (and please let it be organic!). Here’s my though on the matter. When in doubt, don’t have it!
Thanks Marnie for your quick response. I will reach out to the bone broth maker to see how much collagen is in each serving as the package doesn’t specify anything about collagen.
I have been taking collagen to help with joints – wondering what else I can take. I am definitely going to quit. Does anyway have any ideas? I have arthritis in my knees.
There are a number of things you can take that will help with joint pain from arthritis. I will email some information to you today.
Thank you for the article. I asked my oncologist about collagen before I read this article and the studies. She gave me the green light. Now I wonder if she heard me right or I wasn’t clear. Needless to say I have not taken it. I will have a more in depth discussion when I see her. Is there anything other than biotin that you can recommend for skin. I feel like I have aged 10 years in the past 3 due to Tamoxifen.
Hi Heather –
Likely your oncologist is unaware of the studies that have been done. Re your skin, it depends on your age a bit, but skin issues are almost always indicative of things going on in the liver. If you want to improve your skin, do a liver cleanse every 3-4 months, and dry skin brushing also helps improve the texture. Biotin is fine, but liver cleansing is awesome!
Hi marni, thanks for this information. I had just bought Marine collagen on the advice of my dentist to help with recovering from dental surgery. The amount he is recommending is a huge amount and it made me concerned because it seemed like such a nuts amount. Then I found your information. Prior to this I have been taking silica from plant sources which has been making such a different to my eternally weak nails. Collagen is made from Silica, so is there the same issue with estrogen dependent breast cancer and silica?
I’m glad you found the information useful. Re the silica issue, in the research I have read, silica is being used by researchers in nanoparticle technology as a carrier of a drug or therapy to improve delivery, and make the drug more targeted and less toxic for the body. Here is one such study: https://pubmed.ncbi.nlm.nih.gov/34530630/ We do know, however, that silica in crystalline form is toxic to the lungs and can cause lung cancer. The bottom line is: I don’t know. I’m not a scientist. In areas where we don’t know, sometimes it’s just best to abstain – that old saying “when in doubt, don’t” might be helpful here.
What is safe to use for thinning hair as a result of letrozole
I just started taking – Puritans Pride Hydrolyzed Collagen supplement but thought Id check in as I was diagnosed with .2% DCIS five years ago – was hoping it would help with menopause which it has – so you are saying in this article its best I should not take it with my breast issues- ?
Well, it’s always up to you, but I wouldn’t feel comfortable taking it after reading all of the research for this article.
Thank you for searching on the data, I bought collagen supplement yesterday and wanted to start taking it for my joints and hair, I am a breast cancer survivor, now, I decided that not worth to take the risk. My hair is very thin and breaks a lot after the chemos, but I guess I can live with it.