The necessity of iodine isn't exclusive to the thyroid, the entire body needs it. You might say that your body requires iodine the way a car requires oil — it's simply necessary for the entire system to function properly. However, many people don't realize the importance of iodine for women's health.
Aside from the critical role iodine plays in the thyroid, iodine is essential to women in other ways, especially breast health. Women's breast tissue has a high concentration of and a special need for iodine. When breast tissue has low iodine levels, health concerns can follow. Let's take a look at the top six things you need to know regarding iodine and its impact on breast health.
How Does Iodine Impact Breast Health?
1. Iodine Deficiency is a Concern
Iodine deficiency is a concern that affects up to 40 percent of the world's population, including people in North America. One of the primary causes is inadequate iodine intake.
Food has historically been a source of iodine but this has been in decline for decades. Bread is a perfect example. Until 1980, iodine was used to condition dough, but then bromide was substituted. Bromide is a halogen that offers no benefits and competes with iodine for absorption in the thyroid. Fluoride is another example. It's a common, toxic halogen that's present in many water supplies and negatively affects iodine absorption.
2. Healthy Breasts Need Iodine
Every cell, organ, and system in the human body needs iodine, and this is doubly true for female breast tissue. Breast tissue has a high concentration of iodine and the same iodine-transporting proteins used by the thyroid gland.[1, 2] In healthy breast tissue, iodine offers antioxidant benefits. Conversely, iodine-deficient breast tissue is susceptible to lipid oxidation, a contributor to many diseases including cancer.   
3. What is Fibrocystic Breast Disease?
Fibrocystic breast disease is an extremely common and underreported condition in which hormonally-influenced cysts develop in breast tissue. The cysts, which can cause breast pain and tenderness, especially before menstruation, are fairly easy to detect.
Fibrocystic tissue is most often detected during at-home examinations and are often a source of immediate anxiety for the women who discover them and fear the worst. Although fibrocystic breast disease itself is often benign, the New England Journal of Medicine has reported that it is a risk factor for breast cancer. 
4. Fibrocystic Breast Disease is Linked to Iodine Deficiency
Without adequate iodine, breast tissue is susceptible to estrogenic stimulation. That can lead to the production of microcysts, and those can lead to fibrocystic breast disease. Directly depriving breast tissue of iodine can be an immediate catalyst for fibrocystic breast disease.  
5. Iodine Promotes Breast Health
Although birth control is sometimes used to shrink cysts, many women prefer to avoid its associated health risks and instead opt for iodine supplementation. Not only is iodine safe, but it also promotes breast health.
A 1993 study reported that iodine supplementation had reduced indications of fibrocystic breast disease. Research from 2004 found that 50 percent of women who experienced breast tenderness due to fibrocystic disease had an improvement in their situation after iodine supplementation. 
6. Iodine is Even More Important When Breast Feeding
A nursing mother needs enough nutrition to support her own needs and to produce milk for her developing child. Iodine is important for breast health and equally important for normal brain development in children. Iodine deficiency is, in fact, the number one cause of developmental concerns. Iodine is crucial for a newborn brain and breast milk is the perfect means for supplying iodine to a nursing infant.
Are You Getting Enough Iodine?
Getting enough iodine is a product of eating foods that contain iodine and, for many people, taking supplemental iodine. There are several forms of iodine, some are more beneficial than others.
There are tests that can determine if you need iodine and if you do, it's best to compare iodine supplements to make an educated decision as to which is the best for you.
Watch an In-Depth Video on Everything You Need to Know About Iodine
Length: 61 minutes
- Patrick L. Iodine: deficiency and therapeutic considerations. Altern Med Rev. 2008 Jun;13(2):116-127.
- Kilbane MT, et al. Tissue iodine content and serum-mediated 125I uptake-blocking activity in breast cancer. J Clin Endocrinol Metab. 2000 Mar;85(3):1245-1250.
- Smyth PP. Role of iodine in antioxidant defence in thyroid and breast disease. Biofactors. 2003;19(3-4):121-130.
- Venturi S, et al. Role of iodine in evolution and carcinogenesis of thyroid, breast and stomach. Adv Clin Path. 2000 Jan;4(1):11-17.
- Venturi S. Is there a role for iodine in breast diseases? Breast. 2001 Oct;10(5):379-382.
- Stadel BV. Dietary iodine and risk of breast, endometrial, and ovarian cancer. Lancet. 1976 Apr 24;1(7965):890-891.
- Ahad F, Ganie SA. Iodine, Iodine metabolism and Iodine deficiency disorders revisited. Indian J Endocrinol Metab. 2010 Jan-Mar; 14(1):13-17
- Hartmann LC, et al. Benign Breast Disease and the Risk of Breast Cancer. N Engl J Med 2005; 353:229-237.
- Triggiani V, et al. Role of iodine, selenium and other micronutrients in thyroid function and disorders. Endocr Metab Immune Disord Drug Targets. 2009 Sep;9(3):277-294.
- Eskin BA. Iodine and mammary cancer. Adv Exp Med Biol. 1977;91:293-304.
- Krouse TB, Eskin BA, Mobini J. Age-related changes resembling fibrocystic disease in iodine-blocked rat breasts. Arch Pathol Lab Med. 1979 Nov;103(12):631-4.
- MedlinePlus. Iodine. (Last accessed 2013-11-26)
- Ghent WR, Eskin BA, Low DA, Hill LP. Iodine replacement in fibrocystic disease of the breast. Can J Surg. 1993 Oct;36(5):453-60.
- Kessler JH. The effect of supraphysiologic levels of iodine on patients with cyclic mastalgia. Breast J. 2004 Jul-Aug;10(4):328-36.
- Topper YJ, Freeman CS. Multiple hormone interactions in the developmental biology of the mammary gland. Physiol Rev 1980 Oct;60(4):1049-106.
†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.