Is Your Thyroid KILLING You? Breast Cancer

Is Your Thyroid Killing You? Breast Cancer

“Dana, your mammogram results are abnormal. You have unidentified masses in both left and right breasts. You must schedule a follow-up mammogram and ultrasound immediately.”

I approach the large white mammogram machine. A fear like nothing I’ve ever experienced before crashes over me. “Please I need to sit down a moment. I am sorry. I am very afraid.”

The relationship between hypothyroidism and breast cancer has been a topic of debate in the scientific research for over 50 years. Many studies have shown a positive association between hypothyroidism and breast cancer, while others have refuted these findings. This subject remains controversial.

Eighteenth century Austrian monarch, Empress Maria Theresa, passed a law that mandated autopsies be performed on all hospital deaths occurring in the city of Graz, Austria. Many of the people residing in Graz suffered from hypothyroidism and goiter. Broda Barnes in his legendary book Hypothyroidism: The Unsuspected Illness wrote about the data he collected from 26,546 autopsies done in Graz from 1944 through 1958. He wrote in his book that in Graz, where hypothyroidism was endemic, the rate of all forms of cancer was the highest in the Western world.

Back in 1976 in The Journal of the American Medical Association, Broda Barnes published his article Thyroid Supplements and Breast Cancer. He wrote to the editor about his personal unpublished observations on the routine autopsies performed in Graz, Austria. Broda Barnes wrote:1

“Graz is a goiter area; the entire population suffers from a relative thyroid deficiency. Thyroid replacement is rarely employed there. Yet the incidence of breast cancer is as high as ten times that seen in the United States.”

In 2012 a meta-analysis was conducted on 28 related studies. Researchers discovered: 2

“There was significant evidence of an increased risk of Breast Cancer in patients with autoimmune thyroiditis. In addition, the results supported an increased risk associated with the presence of anti-thyroid antibodies and goitre.

While these results indicate an association between thyroid auto-immunity and Breast Cancer, further prospective studies are required to definitively prove causality.”

Breast cancer is currently the top cancer in women worldwide.3 The Thyroid Federation International estimates there are up to 300 million people, majority women, with thyroid dysfunction worldwide yet over half are unaware of their condition. Isn’t it about time a more extensive research campaign is made to investigate this potentially deadly link once and for all?

There are three women in the waiting room when I return from my mammogram and ultrasound. We are waiting for our results. The fear in this room is so intense. A darkness comes over me. Somehow deep within me I know there is real danger and every woman in the room knows it too. I think of my two boys, my husband, my beautiful family members, my friends, and wonder what the world would be like without me. There is a darkness that comes over me. I’ve never experienced it before.

The nurse returns. “Dana, your mammogram and ultrasound results are negative. There is no sign of cancer.” The three other women, who met me only an hour ago, begin clapping. Three strangers are clapping for me. I turn to them and my voice shakes, “Thank you.” I walk out of the building onto the crowded New York City street with tears streaming down my face.

Is Your Thyroid Killing You?

My thyroid has already tried to kill me several times in my 42 years of life – HEART DISEASE and PRE-DIABETES.

On a cold snowy day this very month January back in 2009, my thyroid did succeed in killing my unborn baby, a loss that filled me with so much rage that I created Hypothyroid Mom to warn women about hypothyroidism.

Do you think I wouldn’t take this breast cancer scare seriously? After all that’s happened to me from hypothyroidism, you bet I will take charge of my health and not take any chances. When I was pregnant with my baby that fateful pregnancy, I didn’t do any research on my own and I trusted my doctors unquestioningly. Don’t think I’ll keep my mouth shut this time. Yes there are conflicting results in the scientific research, but the fact that there are many research studies spanning over 50 years showing a potential relationship between breast cancer and hypothyroidism is a red flag. Where there’s smoke, there’s fire.



To all my readers, be an advocate for yourself and TAKE CHARGE of your health. Insist on having your thyroid properly tested including Free T4, Free T3 and thyroid antibodies.

To all the hypothyroid women, be vigilant and proactive about your breast health. Until there is sufficient evidence that proves there is absolutely no risk, don’t take a chance.

To all the breast cancer advocacy groups, please warn your communities of the potential risk and encourage them to have their thyroid tested.

To all the researchers, please take a closer look at the number of studies linking hypothyroidism to breast health. There are multiple studies that warrant further attention and additional study.

To all the doctors, please take a closer look at the current mainstream medical model for thyroid disorder and make change. Please also be vigilant about your thyroid patients’ breast health.

To all my readers, please share this post with everyone you know. Someone you know may have hypothyroidism and not even know it.

To all my cancer survivors, my heart is heavy every time a new cancer survivor joins me here at Hypothyroid Mom. TAKE CHARGE of your health and insist on proper thyroid testing. Be vigilant about your breast health. You are all WARRIORS.

I updated the Hypothyroid Mom Top Resources page to include several great thyroid bloggers. Thank you to each person on this list for creating sites that let us know we are not alone.

  1. Broda Barnes, PhD. Thyroid Supplements and Breast Cancer. JAMA 1976;236(24):2743-2744
  2. Hardefeldt, P.J., Eslick, G.D., Edirimanne, S. Benign thyroid disease is associated with breast cancer: a meta-analysis. Breast Cancer Res Treat. 2012  June; 133(3):1169-77
  3. World Health Organization. Breast Cancer Awareness Month. Retrieved from:
About Dana Trentini

Who knew that little butterfly-shaped thyroid gland at the base of my neck could affect my life so completely? I founded Hypothyroid Mom in memory of the unborn baby I lost to hypothyroidism. Winner of two 2014 WEGO Health Activist Awards: Health Activist Hero & Best In Show Twitter. Connect with me on Google+


  1. Ok Dana, that article was pretty scary :( I had no idea there was a link between hypothyroidism and breast cancer! Is there anything we can do to prevent it?

    • Dana Trentini says:

      Charlene, Thank you for commenting. Unfortunately thyroid disease is an unrecognized underestimated condition by mainstream medicine. It is not taken seriously and doctors often do not keep up to date on it. The fact that there are so many studies suggesting a potential link between thyroid dysfunction and breast cancer is a red flag. Don’t take chances and be proactive.

      The 2012 meta-analysis done that reviewed multiple studies on breast cancer and thyroid disease included in my post, highlights in particular the link with thyroid antibodies and goiter. Recommendations:

      1. Make sure your thyroid is properly tested. Most mainstream doctors rely on TSH alone, however this does not give the full picture. Ensure your Free T4, Free T3 and thyroid antibodies are tested. If you are treated with thyroid hormone replacement drugs and you still don’t feel well, get a second, third, fourth opinion. Check out my post “Top 10 Resources to Find a Great Thyroid Doctor in 2013″. The key is finding a great doctor.

      2. Check for goiters. Thyroid advocate Mary Shomon includes a great article on how to perform a simple self-exam on Thyroid Disease, called the Thyroid Neck Check.

      3. Be proactive about your breast health. I will be including posts on breast health here on Hypothyroid Mom. Given my personal concern about breast cancer, I’ve been in search of the latest news on breast health. Stay tuned.

      • I had an elevated TSH of 5.35 (it showed up after a cholesterol blood test…) The lab’s high end limit is 5…so I am not sure how elevated a 5.35 actually is. I have looked at the multitude of ‘symptoms’ and have many of them…but none seem debilitating to me. (I am kind of liking not having to wax my eyebrows, etc! lol) My doctor said she would prescribe medication…but then decided we would wait six months and do a re-check. (I looked at my old blood tests results and have seen the TSH number rising over the last few years.) My concern is after reading all of your stories and issues I am wondering if I should just leave well enough alone. Not really sure how I should proceed. :(

  2. Thanks Dana!! That was very informative!!! However, what if you have hypothyroidism and are taking the proper medication and you still have thyroid antibodies? What can you do about thyroid antibodies? I noticed that there was a study done on having thyroid antibodies and breast cancer, so that is my biggest concern :(

    • Dana Trentini says:

      Hi Charlene, In addition to treating Hashimoto’s disease patients with thyroid hormone replacement drugs, there are other things to consider.

      Studies have shown selenium deficiency play a role in Hashimoto’s. Get your selenium levels tested and if low ask your doctor to recommend dosage for selenium vitamins.

      Identifying and treating any chronic viral or bacterial infection that may be underlying the immune problem will help.

      Individuals with Hashimoto’s disease often have low levels of DHEA and testosterone. Supplementation under doctor’s care can decrease levels of antibodies if found to be low.

      There is a link between gluten and Hashimoto’s disease, and a gluten-free diet is recommended for Hashimoto’s sufferers.

      Additional factors include:

      Gluten intolerance
      Gut issues
      Adrenal dysfunction
      Viral infections
      Parasitic infections
      Fungal infections
      Chronic inflammation
      Blood sugar imbalances
      Sex hormone imbalances
      Vitamin D deficiency
      Heavy metal toxicity
      Environmental toxicity

      So many factors may underlie the Hashimoto’s condition, which is why the key is finding a great thyroid doctor who works much like a detective to rule out the many different possibilities.

      Given Hashimoto’s is one of the leading causes of hypothyroidism, you bet I will be writing much more specifically on Hashimoto’s at Hypothyroid Mom. Stay tuned!

  3. Hypothyroidism is very strongly involved in Fibromyalgia as well. I never heard the connection to breast cancer until last night during yet more research. This is a scary situation and I wish there were something we could do to MAKE the medical community take another look at hypothyroidism and start treating us properly. It seems like you can’t even see a real doctor anymore. They are all Physician Assistants, or the equivalent. Another excellent resource for info is:

    • Dana Trentini says:

      Hello Karen, Thank you for commenting. You took the words right out of my mouth. I too wish the medical community would take another look at hypothyroidism and start treating us properly. The current mainstream protocol for hypothyroidism is just not working. Thank you for sharing Janie Bowthorpe’s Stop The Thyroid Madness. I love Janie’s website and included STTM on my Hypothyroid Mom Top Resources page. I particularly love the number of online community groups she provides that give members an opportunity to share with one another. Everyone should take a look at the Stop The Thyroid Madness website if you haven’t already.

  4. Hi Dana! First WOW!! I came across your blog through ThyroidThursday….I’m glad I did!! I found a lump in my breast back in 2007, I thought it was a cyst, really wasn’t worried. I went to have a mammogram and they sent me to have an ultrasound. I worked in the medical field for years and knew this was the proper protocol, so I wasn’t worried. I even sent my husband back to work because it was taking longer than expected. I figured once my ultrasound was done they would send me home to wait for my results. That was not the case! The nurse returned and said the dr. wanted to talk to me about my results. My heart sunk! When the dr. wants to talk to you usually does not come with good news. My confidence turned to fear and apprehension, did I really want to hear what the dr. said? I went into his office where he had my mammogram up for viewing. He pointed at the lump and said “this does not look normal”…after that my hearing went, I felt the blood drain from my face, and all I saw were his lips moving. “We have to do a biopsy”.

    I couldn’t think, and I was so pissed that I sent my husband back to work. I just wanted to run out of there. Once out of the building I called my mom and just burst into tears as soon as I heard her voice. I couldn’t get the words out! My family, my son, what would happen if I was sick.

    I had the biopsy and all was well…thank you God!! That was the second most terrifying health related issue I’ve had…and all thanks to my thyroid condition. Thank you for posting your story. I have had this condition for 13 years, and am just learning about all the complications this disease has. I should have been more proactive from the beginning…Thank you again, this really means a lot to me! :)

    • Dana Trentini says:

      Thank you for sharing your story Dawn. I got goose bumps reading your comment because the fear came over me again. It was one year ago and yet it seems like yesterday. It’s time to schedule my mammogram again and I am so scared. I knew that every cell in the body required thyroid hormone for proper functioning in preparing this blog, yet until that experience I had no idea that I was at risk of cancer. When I went through the research on breast cancer and hypothyroidism I was literally sick to my stomach. The lack of awareness is pervasive and this has to change.

      • I hear you on the mammogram…every mammogram is a nervous mammogram. I have a hard time equating my symptoms (fatigue, aches, brain fog… etc.) with my thyroid condition. I have normal TSH levels and have been on Levothroid this whole time. I am now realizing that I need more tests done, and that my symptoms are not in “my head”. My head is swirling right now with years of not understanding my disease, and my husband not understanding my disease. I have a lot to say, but I’m afraid it will be a rambling mess…lol. I have a question: How do I get my husband to understand my disease. I feel like he thinks I’m just making up symptoms, and I feel like I have to act strong, when sometimes I’m just tired.

        • Dana Trentini says:

          It’s not in your head Dawn. It’s not. It’s real. It’s an invisible illness. We look fine on the outside but we suffer so many symptoms on the inside. I would love for you to join me on my Facebook fan page for Hypothyroid Mom. You would find just how many of us there are and how deep the pain runs. I wonder if your husband would find it helpful to read my blog. I know it’s hard to explain to our family and friends how tired we feel and why we don’t have the energy to do things that most people do and it’s not that we’re lazy or unmotivated but just that we are so tired.

          • Oh Dana!! This is not very encouraging :( Did your energy levels go back to normal once you were on the correct dose of thyroid hormone? I was hoping that once I found my sweet spot of T3/T4 combo meds, that my energy levels would get back to normal. If not, is there anything we can do to help with energy?

          • Dana Trentini says:

            Hi Charlene – With proper treatment yes I have much more energy than before, however I am always prone to fatigue especially during stressful times. My whole life I have been more tired than the average person I’m sure due to my undiagnosed hypothyroidism. Proper treatment absolutely helps a great deal however I am very aware that my energy levels are my weak spot so I know how far I can push myself and when I need to step back more as prevention so I don’t overtire myself. Before proper treatment, I was unable to stay awake all day and would fall asleep sitting upright while playing with my son. It was that bad. I am 100 times better now, but I can tell by looking at people around me who are far more energetic that I’m still not the most energetic person.

          • A friend request is on its way. I am definitely going to have my husband read the blogs I’ve found. The blogs and the FB pages I’ve found, Thyroid Sexy, Thyroid Thursday and yours have helped me tremendously…..I am so excited and relieved!! I do feel 100 times better too….for a little over a year I suffered with complete exhaustion, nasal infections, heavy heavy periods, joint pain…the gamut…I thought it was because I was unhappy with my job so I quit!! I worked at it for 10 years!! It wasn’t for another year later a doctor finally tested my thyroid, my TSH was at 13. It took years to get it where it is now, and years of having symptoms and years of my husband saying “but you’re taking medicine!” and me thinking it must be in my head. OMG this is the most I’ve spoke about this to anyone. RELIEF!! So yes, I will have my husband read up on this, and join your FB page. Thank you so much Dana!!!!

          • Dana Trentini says:

            I look forward to having you join me on Facebook Dawn. Absolutely love Thyroid Sexy and Thyroid Thursday. You should also join thyroid advocate Mary Shomon’s FB page. Love them all! So many great thyroid sites online. Dawn, it was never in your head. At a TSH of 13 I’m sure you suffered terribly. I am sorry this happened to you but so happy you are on your way to better health.

  5. p.s. I was not unhappy with my job, and when I think about where I would be today at it, it just makes me sad :(

    • Dana Trentini says:

      Things happen for a reason. Now that you will be healthy and have more energy, you will have the strength and energy level to do whatever you want to do. I know how painful that “hypothyroid tired” feels and it is crippling, so when you are well again and you have your energy back, the skies the limit with what you’ll be able to accomplish.

  6. Dana, wow! I had no idea you’d had this scare so recently. I’m so glad the results of your mammogram were negative. You are such a gift to the hypothyroidism community with your thorough research and understanding of the condition. I’m thrilled others are finding you, and are listening to your story as inspiration for what they can do to be proactive, just as you are. Keep writing and ministering! You’re really, really good at it!

    • Dana Trentini says:

      Thank you for commenting Debra. I love your writing and appreciate the compliment very much! My mammogram experience scared the CR@P!! out of me Debra. I’m due for my follow-up and I’m hesitating to make the appointment because I’m scared. However I know the importance of getting retested and will do it. I’ve had so many family members die of cancer, including my father, that the very word scares me.

  7. Cathy Kopa says:

    Hi Dana:

    I was diagnosed with Breast Cancer 05/11 and after all of the treatments were said and done, they also found Hashimotos Thyroid disease. I often wonder which came first. Is it possible I had an undiagnosed underactive thyroid which led to a poor immune system and Breast Cancer? Or, did the Cancer treatments themselves (radiation specifically) lead to the Thyroid problem. I may never know.

    • Dana Trentini says:

      Oh Cathy, thank you for sharing your story. I wrote this post in hopes of building awareness about the potential danger of hypothyroidism, in particular Hashimoto’s, and breast cancer. My instincts told me that there would be women reading my post with both hypothyroidism and breast cancer. I appreciate you commenting very much. You may not realize but right this moment you have saved women’s lives. There are women out there reading this right now with hypothyroidism who will now pay more careful attention to their breast health thanks to you. Thank you.

  8. my mom has a thyroid problem and this post is making me worry…is there any way to prevent this?

    • Dana Trentini says:

      Hello Dorothy, I am happy you commented. The good news is that with proper thyroid treatment we reduce our risks of the many symptoms that come with hypothyroidism. The problem is that little attention is given to this topic and there are many hypothyroid women in the world who are being treated but who still don’t feel well because they haven’t received proper testing and treatment. Please read this post attached which describes how full thyroid testing should include TSH, Free T4, Free T3, Reverse T3 and thyroid antibodies.

  9. Elizabeth says:

    What about the research showing women with hashimotos have a 60% less chance of
    of suffering with invasive breast cancer, it’s all rather confusing

    • Dana Trentini says:

      Hi Elizabeth, Happy to have you on my site and yes the research on breast cancer is very confusing. The main issue is that hundreds of studies have been done over more than 50 years with some finding an association between hypothyroidism and abnormal thyroid levels, and others show the opposite. In the meta-analysis that I write about in this article, 28 studies on breast cancer and autoimmune thyroiditis (hashimoto’s) and while some supported one side and others supported the opposite, overall the finding was that there was an increased risk of breast cancer with autoimmune thyroiditis. What does this all mean? It all means that more research is needed to make a conclusion however the very fact that there are so many studies showing the relationship, means it’s better to be safe than sorry and anyone with a thyroid condition should be mindful of their breast health and do regular breast exams and those with family history of breast cancer or who suffer breast cancer should all be testing their thyroid. Really what I would like to see is the day when full thyroid blood panels (TSH, Free T4, Free T3, Reverse T3 and thyroid antibodies) becomes part of the standard blood test at every single annual physical.

      • Eva Sekerak says:

        Hello, I was diagnosed in 2o11 with hypothyroidism, few months after in 2012 I found lump in the breast and was diagnosed with stage3 invasive DC with lymph nodes involved. A month ago I was uppgrated to Hashimoto’s thyroditis due to small nodule on my thyroid ( through ultrasound). Why it is so hard for GP to give us full thyroid panel ( blood work) ? I change already my GP once, now I have a doctor lady, but if I didn’t ask to test FT3 and FT4 with the TSH I wouldn’t be tested. Now I am wondering if I should have my antibodies tested, but when I ask my doctor, she said that of course my antibodies will be high because ultrasound suggested hashimoto. Why the doctors are so hard to give us proper testing, is it because they don’t have full knolwedge of Thyroid disorders, or they would loose ‘ their money ‘ if they request full thyroid blood work with our physicals ?!?! Seriously, what is going on !!!!!!!!

        • Dana Trentini says:

          Hi Eva, I wish I understood why there is such lack of interest and awareness about thyroid conditions in mainstream medicine. I share your frustration and feel terrible about all that has happened to you. As you can see TSH does not give a full picture of thyroid health. At minimum testing should include Free T4, Free T3, Reverse T3 and thyroid antibodies, and ideally also include adrenals, sex hormones, and nutrient deficiencies including D3, B12, magnesium, zinc, iron/ferritin and selenium. I have many readers with Hashimoto’s who have gone gluten free (there is a strong link between gluten and Hashimoto’s) and rave about how much better they feel so worth a try. Here are resources if you wish to try it:

          If your doctor isn’t open to full testing, get a second medical opinion.

          • Eva Sekerak says:

            Thank you Dana. About the thyroid ultrasound. They found a tiny nodule in my left thyroid, suggesting the Hashimoto’s thyroidism. No note that it should be biopsied. Should I be worried and have the nodule tested?

  10. I have had hypothyroid since I was 3 years old. I have been on Synthroid or it’s various generic brands since then. I developed stage I breast cancer at the age of 27 and then had a recurrence (into lymph nodes) at age 28. This is interesting, as I may have some link to where my cancer started, considering I have no family history.

    • Dana Trentini says:


      I read your message and stopped a moment. I am sorry about your breast cancer. I’ve had several family members pass of cancer over the last few years and I can only imagine how hard that diagnosis must have been for you. Best wishes to you for continued good health.

      I wish more research was done on the link between thyroid conditions and breast cancer. There is not currently enough research to say for certain but just the same the fact that there are so many studies suggesting the possibility, I hope an article like this will make thyroid patients reading this think about being more attentive to their breast health.

  11. I came across this article while doing an online search for thyroid disease/breast cancer connection. My mother and both her sisters had thyroid problems, two of them had surgery to remove their thyroid gland due to goiters and all 3 of them developed breast cancer, 2 before age 50. I’m wondering what my fate will be because in 2003 I had all but 1/4 of the left side of my thyroid gland removed due to a goiter which was full of nodules and cysts. Now 10 yrs later that 1/4 of gland has grown into a full size gland and has a nodule the doctors don’t like, so going back in next week for a biopsy. Last yrs mammogram caused my first ever call back due to a change from the previous yrs mammogram. Thankfully it was only a cyst! I’m 47 and doctors have told me at this age with hormones starting to fluctuate it has probably caused my thyroid to grow and caused the breast cyst. What do you think?

    • Dana Trentini says:

      Hi Lisa,
      I can only imagine how it must feel to know you have family members who developed breast cancer. Of course this doesn’t mean this will happen to you too, but it is always better to be cautious and just be watchful of your health. As you read in this article there is controversy over this topic in the scientific literature with many research studies showing a link between thyroid abnormality and breast cancer and then many others saying there is no link. So right now there is no definitive answer, however this doesn’t stop me and shouldn’t stop you from being more careful with your thyroid and breast health. First step, be sure you’ve had your thyroid full tested. Here is an article by Stop The Thyroid Madness with a list of recommended lab work. TSH is the one test normally done but it doesn’t give a complete picture of the thyroid condition. Also be sure to do your regular breast self-exams and read all you can about breast health.

  12. Dana:

    I was diagnosed with Hypothyroidism in 1999, and eventually Hashimoto’s Disease a few years later. I have been on Synthroid or other generic thyroid medication since being diagnosed in 1999. I want to state that I had my first baseline mammogram at the ago of 35, and then had annual mammograms starting at the age of 40. All mammograms came back as normal, including the one in May, 2010, less than a year prior to me being diagnosed with Stage 2b infiltrating ductal carcinoma (breast cancer). I have always done monthly self-breast exams, and annually completed my physician’s exam as well. It was in Jan., 2011 when I started having excruciating breast pain in the lower left portion of my left breast which radiated out under my left arm. Finally by Apr., 2011, I scheduled an appointment with my physician’s office, and ended up seeing a woman Physician’s Assistant. After completing the breast exam and marking three spots, she left the room, and then came back to tell me I wasn’t going back to work, but I was to go directly to the Breast Imaging Clinic at the main campus at Sanford Health in Fargo, ND. She tried to reassure me that it could be a cyst or other issue, but that I needed to be seen immediately. I have two sisters, who were both in the middle of work-related duties, and my Mom lives 200 miles away, so she called my brother-in-law to come and get me and to sit with me while I waited to be worked into the system for an ultrasound. When the technician finished my ultrasound, she left the room to speak with the radiologist on duty. Following a few minutes, the radiologist came into the room with the technician, and they started to redo the ultrasound again, because my breast tissue is so heavy and dense, and it was difficult for them to see what they were looking for from the scan. Once they completed the ultrasound, the radiologist indicated that I would be scheduled for three needle biopsies as soon as possible, which was the following Monday. The radiologist completed the three needle biopsies the following Monday, and told me that I would hear back from her no later than Wednesday. However, it was the next day on Tuesday afternoon that she called to tell me I had breast cancer in all three areas from the biopsies – two lumps and one large lymph node. Within 1\2 hr., I received a call from the Sanford Health’s Roger Maris Cancer Center scheduling me into their system and preparing me to fight through a 9+ breast cancer battle. I had a double lumpectomy, removal of nine lymph nodes, 16 chemotherapy and 33 radiation treatments. I am continuing to recover at this time, and after much encouragement from many people, I published my journey in a book entitled, “Boundless Blessings and God’s Grace – My Journey through Breast Cancer” by Cynthia J. Eggl. I published my journal to give encouragement to others that should they get this diagnosis, they too could make it through this challenging, life-threatening ordeal. What has bothered me the most was that I was the first person in my family diagnosed with breast cancer, and I was so proactive in watching my breast health, and yet it took extraordinary pain to get me to the doctor’s office. Once the tumors and lymph nodes had been removed, my breast surgeon and medical oncologist both stated they felt the cancer had been growing for 2-4 years. Needless to say I do feel I am a better person for having gone through my breast cancer battle, and I truly do feel I am blessed to be here and to share my story. I too wonder, however, if there is a link between the Hashimoto’s and my breast cancer. Your thoughts?

    • Dana Trentini says:


      I had to put my head down on my desk after reading your story for how upset I am for what happened to you. I am very sorry to hear this. I am touched by every cancer survivor who contacts me. Congratulations to you on your book. You will give hope to others and will change people’s lives. Are you on Facebook or Twitter to share your story with my readers?

      There are decades worth of research supporting the connection between hypothyroidism, in particular Hashimoto’s (thyroid autoimmune disease), to breast cancer. However there are also many studies refuting it. I’ve also found research although much less of it linking hypothyroidism to breast density. I too have dense breasts which is what was picked up on my first mammogram as suspicious. Dense breasts make it more challenging for the mammograms to pick up on breast cancer.

      Absolutely I believe there may be a connection. The sad part is that like your story a person can do all the right testing and self-exams and still not catch it until much later stage. One thing I know for certain is the importance of checking that your Hashimoto’s is properly managed. In case there is a link, then properly managing it is even more important.

      Best wishes to you. I am honored to have you at Hypothyroid Mom! Congratulations on your book “Boundless Blessings and God’s Grace – My Journey through Breast Cancer” by Cynthia J. Eggl.

  13. Hello. Interesting article. I have had Hashimoto’s disease since my mid 20′s and Fibromyalgia since my late 20′s. I strongly believe there is a connection between ongoing TPPO antibodies and Fibromyalgia. Here are some studies where the inflammatory cytokines match up:

    Regarding the connection between breast cancer and Hashimoto’s–Could it possibly be high levels of radiation that is causing both? Breast tissue, Thyroid tissue, and prostate tissue are the most sensitive to radiation. I am wondering if this Graz Australia isn’t sitting right under the old Ozone hole.

    • Dana Trentini says:

      Hi Becky,

      Thanks for sharing those research articles with me. I just saved them so I can read them more carefully. Absolutely I believe there is a connection between hypothyroidism in particular Hashimoto’s and Fibromyalgia. In fact I’ve been researching that link for an article I am posting here at Hypothyroid Mom at the end of July on that very topic. Stay tuned.

      Fascinating your suggestion about radiation. It’s very possible that the cases in Gaz were environment specific to that area. I wish more attention was given to this topic by researchers because it could be life changing for so many women.

  14. Samantha says:

    Hi I am 21. I have read your article and I found it very helpful, but about 8 months ago I was told my tpo levels were too high. The reference range for my labs were 0-30 but my results said 589 and I’m not sure what this means my previous doctor did nothing for it. And I’m not sure if I need to to go have it checked again or just wait it out.

  15. Hi. I have a goiter and hashimotos and survived breast cancer in 2010. Thank-you for the info!

    • Dana Trentini says:


      I am touched by every cancer survivor that joins me at Hypothyroid Mom. You are a warrior. Best wishes for your continued health.

  16. Charlotte says:

    Out of curiosity, I googled Hashimoto’s and breast cancer and found your site. I also read about the possible connection to miscarriages. While very enlightening. I admit I’m somewhat numb as I read, however. I was diagnosed with Hashimoto’s around seven or so years ago and take Synthroid daily.

    It always affects me to say I’ve been pregnant seven times and have four children. All miscarriages were around the end of the first trimester and a laparoscopy/hysteroscopy was done which didn’t indicate any issues. When my last pregnancy was confirmed, rather than feeling joy, I experienced terror as I so didn’t want to have to go through yet another loss. Thankfully, I didn’t, and my now 19 year old daughter has been at my side as I have battled breast cancer that was diagnosed in January of this year. I had a mastectomy in March and just yesterday completed the last of my major chemo. I will continue Herceptin infusions through June of 2014 and then I believe my port will be able to be removed. Things went awry when it was placed and I spent a week in the hospital with a collapsed lung. (I was discharged on a Friday afternoon and began chemo the following Monday morning.) I will also start the five year regimen of Aromacin at the end of this month.

    Thank you ever so much for your endeavor to educate and support the countless women who may be affected in this way. You can bet that I will be speaking to those in my medical community to see how they respond.

  17. Elizabeth J. says:

    I am the 3rd generation in a row (myself, mother, grandmother) to have hypothyroidism. Mine has been diagnosed as Hashimotos. I am also the third generation in a row (same as above) to have breast cancer.
    A few years ago I changed doctors specifically to get better thyroid treatment. New doctor tested antibodies, T3, T4, all of which had never been tested. But she also tested vitamin D levels because she said it is very common for people with hyperthyroidism to have low vitamin D. Since getting breast cancer, I have found out that low vitamin D is also being looked at as a possible risk factor for breast cancer.

    • Dana Trentini says:


      I put my head down on my desk after reading your story. I’ve researched this connection with breast cancer and as you know from my article it is a controversial topic. Yet my instinct tell me there is a connection. Your story shows that so clearly. Elizabeth, I plan to write more about the connection in future articles at Hypothyroid Mom. May I use this comment in a future article. I would not include your name if you prefer.

  18. I just had a lumpectomy and radiation treatments for breast cancer. During my pre-testing it was discovered that I had multi-nodules on my thyroid as well as hypothyroidism. They just started me on 75 mg of synthroid. Thanks to your site, I will not take another pill until I have a complete thyroid work-up and iodine level checked. Funny, I asked my doctor if there was any correlation between breast and thyroid cancer and he said he didn’t know of any. Yet, it has been a controversy for over 50 years! He wants to do a thyroidectomy with life long hormone treatment. 23 years on 1 mg. of estrogen was bad enough. Sad, we have to investigate for ourselves everything we are told by our doctors. Thanks for the Internet!

  19. Hello!
    I am 21 years old and was recently diagnosed with hypothyroiditism, so far only one antibody was tested (negative), doctors refuse to test the others. I’m currently taking 75ug Thyroxine, but though my results are really good, I still feel very tired and worn out and have difficulty losing weight (I’m in the upper range of normal, so I’m drecieving no assistance from my doctor), as well as severe eye symptomes, so overall I’m not happy. I’m starting a self-treatment with Selenium (no worries, I know high dosages are toxic) and hope I will get a bit of relief.
    However, this post really scares me. I’m at a higher risk for Breast Cancer anyways because my mother already had it and my grandmother died from it… If I could, I’d just have my breasts taken off, end of discussion. I don’t like them that much anyway.
    Thanks for your blog, for the first time I really feel understood in regards of my condition. I also had hypothyroiditism symptomes loooong before I got a diagnosis and thought this was abnormal… I wish I’d know what to do to live my life like a normal young person does, but I’m usually too tired to do much.

  20. I had symptoms of hypothyroidism that were misunderstood by both the doctors and myself in 2009. My hair was falling out and my periods were rare and heavy when they came. My gynecologist insisted it was menopause. I was 52. My gnp basically ignored me.
    My gyno tested my hormones and confirmed it wasn’t menopause but this was all put on the back burner by a mammogram that resulted in my having breast cancer.

    After my treatments of surgery and radiation therapy I went back to address the missed periods. I was now in menopause (Tamoxifen) but had a thick lining in my uterus. I thought “well yeah , I have had two periods in the past 2 years. Now. I have hyper plasia. Good god what else…never say that again.
    I had many symptoms that were similar to the symptoms of menopause and post radiation treatment. Exhausted, massive hair loss, weight gain. leg cramps…
    Lets test your thyroid…what do you know….I get a script in the mail and paperwork that my cholesterol is 208, it was 140 and my thyroid test came back abnormal.

    Thanks Doc!

    I went into detail for anyone else with similar concerns. I can’t help but wonder what came first the chicken or the egg. My first symptoms make me think the hypothyroidism!

    • Dana Trentini says:


      I am so sorry to hear about your breast cancer. I am touched by all the cancer survivors who join me at Hypothyroid Mom. I wonder too how little research has been done on this potentially deadly link between hypothyroidism and breast cancer and how the time has come to build awareness and try to empower us to be advocates for ourselves. Best wishes to you for good health. Thank you for sharing your story. It is so important because I know that I have many readers who read the comments but may not comment themselves but learn for the stories shared just the same.

  21. Good Morning,
    My mom has cancer in the same breast, first time was 8 years ago, they told her labs were fine but when they arrived today for the removal the Ana MD refused to do the surgery due to her throyid level, how long will that take to get within normal limits to have the surgery

    • Dana Trentini says:

      Serena, I apologize for the delay in responding. Over the months of December and January I’ve had close to 4 million visitors here and on my Hypothyroid Mom Facebook page and struggling to get to everyone. I am very sorry to hear about your mother’s cancer. I don’t think there is a specific time that I can give to how quickly her thyroid can be brought back in range. However what I would recommend is that she have a great thyroid doctor look at her thyroid condition.

  22. Thank you so much for posting this. I was diagnosed with hypothyroidism about two and a half years ago after my second child was born. I could not explain the excessive fatigue within a couple of hours of being a work. I felt like I could go back to to sleep. My periods were lasting a week and more often and heavier. This went on for almost a year and I could not lose my baby weight. I felt bloated all the time and I wasn’t overeating. I was also working out with no results. I finally went to my regular physician and he requested blood work and sure enough, my thyroid was slow. My doctor sent me to an endoctrinologyst who prescribed 75 levothroyid, which I have been on for almost two years. Now I am super worried that down the road, I will get cancer. I am only 35 and have relatives with cancer on my paternal side. Thank you for the article and I will look out for my health even more now.

  23. Hi Dana. After 30 years of thyroid problems and now Hasitoxicosis, I am scheduled for a thyroidectomy on 9th January here in Brisbane, Australia. As it was that time of year for me again I popped along for my yearly mammogram to get it out of the way – was told there is calcification abnormalities and I have to have a vacuum core biopsy. Luckily my thyroid surgeon is also a breast surgeon – so with the help of my GP I am going along to see the surgeon on the 6th January to,discuss which to give priority to and what track to take.

    • Dana Trentini says:

      Hi Andrea, I apologize for the delay in responding. I’ve had close to 4 million people visit my site and my Hypothyroid Mom Facebook page the last few months and struggling to get to everyone. Your thyroidectomy may have already occurred and I hope your recovery is going well. I’m sorry to hear all you are going through. Here is information from thyroid advocate Mary Shomon on recovery from thyroid surgery.

  24. Im really glad I came across this blog . I had no idea of the association of hypothriodisim and breast cancer and my husband never said anything about it (maybe not upset me)My sister has an autoimmune disease SLE and I have Hashimotos disease which autoimmune aswell so I think theres something genetc running in the family re autoimmune diseases.Eveything started with the classic symptoms of hypo and now I also have insulling resistance, aldosteronizim and cholestrol along with it. Although theres never been breast cancer in our family Im really horrified about the lumps in my breast which I discovered 2 days ago. My husband who is a GP has booked my in to see a surgeon and have a mamogram etc for tommorow. I have this pain in my left breast, my husband said it could be a cyst or if it is a tumor cancer it could be close to a nerve which is giving me pain. The pain I noticed about 2 weeks ago which was light but I think because I know theres lumps it kind of feels a bit worse. Im kind of excited about tommorow and horrified at the same time and confused.

    • Dana Trentini says:

      Hello Emma, I apologize for the delay in responding. Over the last two months I’ve had close to 4 million people visit here and on my Hypothyroid Mom Facebook page and I’ve struggled to get to everyone. I’m sorry all you are going through. I assume by now you’ve had your mammogram to determine the cause of your breast pain and to have a closer look at the lumps you feel. Prayers for you. I hope it all turned out okay.

  25. I just had a baby and now there is a knot in my thyroid. I also have cysts in breast

  26. Hi Dana.
    I am brand new (yesterday) to the diagnosis of hypothyroidism but age old to all of it’s symptoms. It took 9 years (and a symptom that you can see…face scarred and currently with gross acne and blemishes) to find doctors to take me seriously for symptoms of major fatigue, muscle/joint pain and weakness, etc. (Have had narcolepsy with cataplexy for 16 years which complicated/confused finding answers.) Thank you for providing a personal atmosphere to learn and question our health issues as we struggle to understand and find peace with the information (and lack of) available….

    My mother died of breast cancer at the age 40. She was diagnosed at 38. Cancer did not show up in mammogram due to the density of her breasts(which I have as well). When retested, after having frequent fainting spells and pain in her chest (first explained to be Costochondritis) it was stage 4 when diagnosed. To my knowledge she had no other health conditions, though she did battle with huge bumps on her face. Also, my fathers mother and sister have had breast cancer as well at young ages. I have always been told to absolutely stay away from hormones. I am 44. I started menopause after having cysts and one of my ovaries removed a few years back and never considered hormone treatment. I have now been prescribed Synthroid and Aldactone. I am terrified to start taking these medicines, even though my doctor has said they are not related to the hormones that are thought to provoke breast cancer. Any thoughts/knowledge about my situation would be so appreciated.

  27. Just. found out I have 3 thyroid nodules. One is larger than the other two. I had 7 biopsies done on the three last week, thankfully results were negative…at least on the nodules they could get specimes from. The larger one the doctor could not get specimen, it was extremely tough. Couple years ago a small mass was found in one of my breasts. I see a breast doctor after yearly mammogram each year to see if any change. No biopsy every performed on lump, but no change either. The large thyroid nodule is on the same side as the breast lump. I am just a little concerned about the thyroid nodules and the lump in breast. Just would like any comments or suggestions. I see the endocrinologist again in 6 mos to see if any change….but still concerned.

  28. Maile Chatlos says:

    I am so glad this blog came across my path. A girlfriend of mine shared a photo from your FB page and it popped up on my feed. I was diagnosed 8 years ago after my first son. Anyways, I meandered over to your page and it directed me here. I had no idea that a website like this existed!! Thank you for starting it. People really don’t understand thyroid ism at all. They think it isn’t a big deal and sort of treat me like I’m nuts. I recently had to have a benign tumor removed and never considered it possibly having anything to do with thyroid. I have three boys, my last two pregnancies were considered high risk because of thyroid. But between my middle and youngest boy I suffered a heartbreaking miscarriage. No one even hinted to the possibility of a connection between the two. Your website is very informative. Thank you.

  29. Peggy Forster says:

    I am so glad I ran across this webpage. I am 40 years old and recently was diagnosed (after the fact/hysterectomy) with endometrial/ueterine cancer. After a pet scan they confirmed that my thyroid AND breast both have tumors- which I have had 2 ultrasounds done this week along with major blood work for the thyroid. They are now wanting a biopsy on the breast. I have not heard back re: the thyroid yet. I asked my GP if there is any correlation and he said let’s see what the tests say but if that was the case I would be “more” sick.
    Your thoughts??

  30. I am so glad I ran across this webpage. I am 40 years old and recently was diagnosed (after the fact/hysterectomy) with endometrial/uterine cancer. After a pet scan they confirmed that my thyroid AND breast both have tumors- which I have had 2 ultrasounds done this week along with major blood work for the thyroid. They are now wanting a biopsy on the breast. I have not heard back re: the thyroid yet. I asked my GP if there is any correlation and he said let’s see what the tests say but if that was the case I would be “more” sick.
    Your thoughts??

  31. Hi Dana,

    I was diagnosed with hypothyroidism during pregnancy in 2010. Since then I have been on thyroxine 50mcg. I had no symptoms at all. I was in hands of good endocrinologist who treated my gestational diabetes. In January 2010 I went for an ultrasound of my breasts because I felt a lump. Add on mammogram did not show anything due to dense breasts. I had biopsy and lumpectomy, diagnosis are stage 1 invasive ductal carcinoma. I never thought I should be worried about breast cancer, I am 37. I had suspicion that the cancer was triggered by IVF. After reading your blog, I have new suspicion..

  32. I really loved ur Story on here. I am 35 years old and recently had my thyroid tested as well as a thyroid ultrasound. My GNP felt my thyroid and noticed it was enlarged. The only one in my family that has been diagnosed with thyroid problems is my mom. My Vitamin D is an 18. Now I have to see an endocrinologist sometime. Breast cancer runs on both sides of my family bad so when should I start having a mammogram? I’m kinda scared bc where it runs bad on both sides.

  33. Jill Griffiths says:

    We all know that thyroid medication can cause throat cancer, lung & breast cancer.. It can cause so many other problems – it can ruin lives. For me –38 side effects some of which I still have and can only get rid of them with surgery which I will have to pay for myself. I can’t take any thyroid medication. It ruins skin, puts on weight, messes with the brain, causes aversion to exercise, does not give the energy back it is supposed to, depletes the adrenal glands (even further if they were not firing on all cylinders to start with). All this is because the initial testing is insufficient. There is no questionnaire, no other tests — especially the adrenals (CT scan required NOT cortisol blood test – unreliable) no questions about previous hormone problems, are you on HRT, the pill, etc. Anaesthetics & thyroid medication do NOT mix as I discovered to my cost. There were times when I thought I would die – I was scared. And now — well, the NHS turns its back and walks away. I’ve been left to pick up the pieces. This is BAD patient care, bad housekeeping, and breaks the Hypocratic oath. There are those whose marriages have collapsed, they can’t work anymore so live off the state, drive only short distances. don’t drive at all because the effect of the medication on the brain.. Some have nearly died, some committed suicide. Men have grown breasts!. Were they able to get that fixed? If so, was it because they were men or, because of what had happened? I couldn’t get anything done. This could go on and on. Forums are required around the country to discuss this enormous problem.

  34. Dana Trentini says:

    Thank you Health Wealth Builder for including Hypothyroid Mom on your site. Much appreciated.

  35. Victoria Brates says:

    Hi Dana,
    First of all, I like the way you write and the care you show in each line. I live in the UK, not that it makes a difference in the health problems we encounter, just the protocols we follow. I discovered problems with my parathyroid glands in2006 and during an ultrasound of the neck I was told I have many nodules around my thyroid gland. Nothing to be worried about, I was told. In 2011, I started treatment for breast cancer. Now I am following hormone treatment. Following a complaint connected to a strange feeling when swallowing, I was diagnosed of having goitre, which didn’t worry me until my GP (here, everyone has to be seen first by a general practitioner) suggested I should go to be checked by a ENT specialist. They wanted to do a biopsy as one of the nodules is very big and they think it might be cancerous. I will have to have the test next month so am a bit worried. I never thought breast cancer can be connected to the thyroid gland!

  36. I just went through biopsies & a lumpectomy for Atypical Ductal Hyperplasia which is precancer of the breasts. I’ve had hypothyroidism for 27 years. I have Hashimoto’s thyroiditis. I have vit D3 def, osteopenia, severe vaginal scar tissue, fatigue, gum problems, plaque on my teeth, severe chronic cough that my dr says is acid reflux. So many other problems. I feel like I m dying a slow death with constantly

  37. Dana Trentini says:

    Victoria, I am sorry to hear all you’ve been through. I hope everything turned out okay with your thyroid biopsy. I have a large following of thyroid sufferers from the UK. I hear their frustration with the medical system and it is so upsetting. Thyroid awareness is needed around the world and I’m happy to have readers from across the globe. Prayers for you.


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