Relationship Between Thyroid Disease and Breast Cancer

February 24, 2009

Relationship Between Thyroid Disease and Breast Cancer 

 Competency # 16 Minerals                   ReferenceGiani Jr. Clin Endo Metab 81, 990 1996

Why on earth is there a relationship between thyroid disease and breast cancer?  What’s that about?  This is a controversial topic, but hints at an intriguing role in which iodine is the lynchpin between cancer and autoimmune disease and may explain why we need so much more. 

 The skinny goes as follows.  If you take an ultrasound to measure the volume of a thyroid gland in a woman with breast cancer, you will find a volume of about 21 cc.  Now, take the volume of a woman with fibrocystic breast disease, and you get a volume of about 14 cc.  A woman with normal breasts has a 12 cc thyroid.  If you take a person with a massive thyroid (a goiter) and give them iodine, it will shrink down dramatically.  

So, what really happens is that all of us will have a swollen thyroid when we don’t get enough iodine, and a tiny thyroid is a normal thyroid.  It should be noted that all the women in the above study had normal thyroid blood tests like T4 and TSH. Now, if you examine women with breast cancer for overt thyroid disease you find that 46% of women with breast cancer have some evidence of thyroid disease like Hashimoto’s thyroiditis.

  Control group women only have 14% incidence of thyroid disease.  Explain that! Well, here is the explanation, in the form of conjecture.  Iodine was evolution’s first anti-oxidant, as we learned last week.  It continues to function in our cells as an antioxidant.  Its role has expanded to that of a gene stimulator and marker.  It turns genes on and off that are part of the estrogen sensitivity group making us more “resistant” in sum to the estrogenizing effect of our environment (with plastics, BPA etc).  

It is known to coat many proteins to help protect us from autoimmunity.  It is also highly taken up by breast ductal cells.  Those are exactly the cells that turn into the most aggressive and incurable breast cancers.   If we don’t get enough, those cells may start running amok.  The connection of iodine deficiency and autoimmunity is manifest in the thyroid-breast cancer connection.  But it has other effects.  Iodine is taken up by the lining of our stomachs (that secretes gastric juices) and our salivary glands, our tear glands, the cells that make our cerebro-spinal fluid. 

 So, if you do an iodine-loading test (give 50 mg of iodine a day to see how much you pee out) and then collect urine for 24 hours, it takes people 6 months on average before they begin to pee out 95% of what they take in.  That suggests that our bodies really want hundreds of mg. of iodine in reserve, not the 1 or 2 mg. that our thyroid alone takes up.  Maybe our thyroid is only just one of our iodine storage sites.  Of note, the 4000 women in the “Iodine Project” who did the loading test reported feeling better energy, sleeping better, having clearer thinking…. all signs of better thyroid function. 

 WWW.  What will work for me?  All our glands that secrete things seem to need iodine.  Men have those too.  Do they swell up in men too?  There is very little proof about iodine in anything except breast disease and thyroid disease.  Does this apply to men?  Is it toxic?  How can I get it if I want to give it a try?  Next week.

This column written by Dr. John E Whitcomb, MD, Brookfield Longevity, Brookfield, WI (262-784-5300)