From What Your Doctor Fails to Tell You About Iodine and Your Thyroid by Robert Thompson, M.D.

I’m going to make a bold statement here: Iodine shortfalls coupled with bromine and other toxic halogens cause fibrocystic breast disease and breast cancer.

Breast tissue contains the body’s third highest concentrations of this essential mineral, so shortfalls in iodine needs have a highly negative impact on breast tissue. When you don’t have enough iodine in your diet, or when you are iodine compromised because of exposure to the toxic halogens chlorine, fluorine and bromine, the breast and thyroid compete for the little iodine that is available. The result is that the iodine supply in the thyroid and breasts is depleted, opening the door to thyroid related disorders, fibrocystic breast disease and breast cancer.

Fibrocystic breasts or fibrocystic breast disease

This condition has become so common that some doctors argue it isn’t a disease at all. More than half of all women experience fibrocystic breasts and cyclic breast tenderness at some point in their lives.

Women with fibrocystic breasts have bumpy, lumpy breasts that may have hardened areas. They are sometimes painful. Pain has been linked to hormone fluctuations during the menstrual cycle, caffeine intake and the use of oral contraceptives.

Ropy scar-like tissue or cysts and lumps characterize fibrocystic breast disease. Many women have both symptoms and some have nipple discharge as well. The lumps and bumps generally change throughout a woman’s menstrual cycle. A lump that does not change during a menstrual cycle or on a postmenopausal woman who is not on hormone replacement may signal another problem and requires further investigation.

Most professionals agree that fibrocystic breasts do not increase your risk of breast cancer, except in women with another risk factor, such as family history of breast cancer or other genetic predispositions to the disease. Some medical practitioners argue that the lumpiness of fibrocystic breasts may make it more difficult to feel potentially cancerous lumps in a breast self-examination (BSE).

Fibrocystic breasts are usually quite dense, so they are somewhat resistant to mammograms, so many women with this condition are referred for diagnostic ultrasounds that can more easily distinguish between healthy and diseased breast tissue.

However, there is a common thread between fibrocystic breasts and breast cancer: Both conditions are related to insufficient iodine intake and halogen toxicity.

Several studies in animals and humans give strong evidence that:

  • Animals that were intentionally deprived of iodine developed fibrocystic breasts.
  • Supplementation with iodine reduces the lumps, bumps and hard spots and even reduced breast size in animals. Just taking 6 mg of iodine a day for six months stopped the pain of fibrocystic breasts for half the women in a 2004 study reported in the journal Breast.

I am convinced that bromine’s interference with iodine also contributes to endometriosis and pelvic pain.

Estrogen, iodine and breast cancer

Iodine deficiency causes estrogen production to become unbalanced and dysfunctional. At the same time, this double whammy causes breast tissue to be more sensitive to estrogen, cystic changes occur, increasing the risk of breast cancer. That’s a double-barreled shotgun.

Today, one in seven American women will develop breast cancer during her lifetime. Compare that to 30 years ago, when iodine consumption was much higher, bromine use was much lower, and one in 20 women developed breast cancer. Women in Japan who consume high amounts of dietary iodine have much lower rates of breast cancer and thyroid problems. However, when women emigrate from Japan to the United States and begin eating a Western diet, with its fractional amount of iodine and loads of bromine exposure, their incidence of breast cancer and thyroid disease increases dramatically.

Interestingly, the 50% drop in our national iodine levels since the 1970s parallels the increase in breast cancer rates, despite the National Cancer Institute’s contention that the higher rates are due to earlier diagnosis and an aging population. The drop in iodine levels and the steadily rising breast cancer rates—and what Dr. David Brownstein calls an epidemic of hormone-sensitive cancers like breast cancer—are simultaneous with the removal of iodine from refined flours and the substitution of bromine, which blocks the body’s absorption and utilization of iodine. These are too many “coincidences” to be disregarded.

Another interesting noncoincidence is that the incidence and severity of breast cancer is lower in Japan and Europe than in the United States, attributed to dietary differences, the lack of bromine in refined flours and the absence of fluoride in municipal drinking water. For example, less than 1% of public drinking water is fluoridated in Japan, and virtually no European countries fluoridate their drinking water. Potassium bromate, the form of bromine routinely added to flours in the United States, is banned in the European Union, and Japanese flour manufacturers voluntarily stopped using potassium bromate in their products in 1980. One Japanese company resumed using the iodine-blocking toxic halogen in 2005, but most of Japan’s flour is still bromine free. The absence of these Black Hat halogens from the lives of Japanese and European women offers powerful protection against breast cancer.

A final non-coincidence is our rising exposure to xenoestrogens—environmental estrogens present in plastics, pesticides, meat and dairy products—that trigger further estrogen imbalances.

It is impossible to ignore the weight of the evidence against the conscious addition of toxic halogens to our food supply, contaminants that have been scientifically proven time and time again to deplete iodine stores, disrupt iodine function and cause a variety of diseases, including breast cancer. I am convinced that bromine’s interference with iodine also contributes to endometriosis and pelvic pain.

Dr. David Brownstein says, “Perhaps rectifying iodine deficiency will be the missing piece of the puzzle to solving the riddle of breast cancer.”

He adds, “I believe all women need to be evaluated for their iodine status before they reach the stage of breast cancer.”

Dr. Brownstein has documented numerous cases among his patients that demonstrate that iodine treatment reduced breast cancer tumor sizes and induced remissions with no other treatment than the use of iodine.

Let’s step back for a moment and take a look at the role of estrogen and iodine in breast health or ill health.

Estrogen is a sex hormone predominant in women, produced primarily by the ovaries, with smaller amounts produced by the adrenal glands and fat tissue. Excess estrogen stored in fat tissue is considered a risk factor for breast cancer in women.

Men do produce small amounts of estrogen, about 10% of the amount found in women, mainly made by the adrenal glands, fat tissue and liver. And, by the way, men can and occasionally do get breast cancer and the incidence of breast cancer in men is rising dramatically.

Just a quick primer on human estrogen: There are three types of estrogen: estrone, estradiol and estriol. The weakest of these, estriol, stimulates breast tissues less than estrone and estradiol. In fact, there is a growing body of research that confirms that estriol protects against the cancer-causing effects of estradiol and estrone.

In an important 2002 study from the U.S. Army and performed at the Public Health Institute, Oakland, California, researchers compared estriol levels during pregnancy with the occurrence of breast cancer in the same women 40 years later. Of the 15,000 women entered in the study, those with the highest levels of estriol relative to other estrogens during pregnancy had the lowest cancer risk. In fact, women with the highest level of estriol during pregnancy had 58% lower risk for breast cancer compared with women who had the lowest estriol levels. The researchers also noted that Asian and Hispanic women had higher estriol levels compared with other racial groups, an interesting finding since Asian and Hispanic women have the lowest breast cancer rates.

The researchers concluded, “If confirmed, these results could lead to breast cancer prevention or treatment regimens that seek to block estradiol estrogen action using estriol, similar to treatment based on the synthetic anti-estrogen tamoxifen.”

So where does iodine come into this equation? Research from Jonathan Wright, M.D., a bioidentical hormone therapy pioneer, shows that iodine helps maintain the correct balance of the three types of estrogen and even to convert them into safer estriol.

Estrogen balance is impossible to maintain when there is iodine deficiency present,” writes Dr. Brownstein.

Breast cancer

Now that we’ve established the incontrovertible link between iodine and estrogen balance, it’s easy to see how a lack of sufficient iodine and bromine interference causes runaway estrogen levels leading to breast cancer.

Bernard Eskin, M.D., of Drexel University in Philadelphia, one of the foremost researchers in the field of iodine and breast cancer, conducted animal research in the field for more than 40 years. His work gives us some pivotal basic truths about iodine and breast health:

  1. Long-term iodine depletion causes changes in breast tissue.
  2. When sufficient iodine is added to the diet, breast tissue returns to its normal state.
  3. Normal iodine intake results in normal estrogen function in breast tissue.
  4. Iodine supplementation blocked the development of cancer in animals given cancer-causing substances.
  5. Molecular iodine, like that found in kelp and other forms of seaweed, is the most effective form of the mineral for the treatment of all types of breast disease. However, most people do not have kelp in their normal diets, and the amount in kelp varies according to conditions. In addition, laboratory testing has shown high concentrations of heavy metals in kelp and other sea vegetables. That is why it is better to use a supplement when dealing with specific diseases that respond to iodine.
cancer cell

Simulated image of a cancer cell.


Here are more exciting research results showing the connection between low iodine levels in the body and breast cancer:

  1. Iodine supplementation desensitized estrogen receptors in breast tissue, meaning iodine gets to cells where it is needed rather than being “bumped” by toxic bromines.
  2. Iodine caused cancer cell death (apoptosis is the medical term) rather than wild reproduction of cells characteristic of cancers of all types.
  3. It also caused more cancer cell death than the commonly used chemotherapy drug, Fluorouracil, also known as 5-FU, which has numerous and debilitating side effects.

Iodine has also been shown to increase the activity of the BRCA1 gene that helps balance estrogen activity in breast tissues and even to increase the effectiveness of the breast cancer drug tamoxifen and decrease resistance to tamoxifen.

Throughout this book, I’ve mentioned several types of iodine: potassium iodide, sodium iodide and molecular iodine from kelp. A great deal of research suggests that molecular iodine is particularly helpful in established estrogen balance and even reversing breast cancer.

Several studies show that adding seaweed to rats’ diets reduced the rate of breast tumors, stopped the growth of existing tumors and caused cell death in three known breast cancer cell lines, leading Dr. Brownstein to write, ”You cannot give breast cancer to rats that have sufficient iodine.”

Whenever I do a lecture on iodine, I am asked about dosages and whether 12.5 mg or more isn’t too much. Years ago, we thought that 400 IU of vitamin D a day was more than adequate. Yet we live in a toxic world that is more toxic today than it was just 20 years ago.

Iodine is going along the same path as vitamin D. There is no research showing that 150 mcg of iodine is sufficient and our exposure to Black Hat halogens is far more than ever before in history. We live in a chemical environment and we need more vitamins and minerals.

Bear in mind that dosage levels vary. Your thyroid alone needs approximately 5 mg of iodine per day, but since we know that iodine is used by the cells of the breast, ovaries, uterus and prostate, higher dosages are warranted for almost everyone. A useful dosage for an adult would be 12.5 mg—that’s enough to keep your thyroid functioning and to help the other iodine-hungry tissues, including breast, ovaries and skin. For the higher dosage of iodine, recommended by holistic physicians, you’re looking at up to 50 mg per day based on an iodine loading test. The higher doses are often done under the supervision of integrative practitioners. (See Chapter 8.)

Dr. Guy Abraham, a UCLA professor, pioneer in iodine therapy and leader of the Iodine Project that researched the many needs for and uses of iodine in the human body, was a proponent of iodine supplementation to prevent breast cancer. He said it takes 20 to 40 times the amount of iodine to control fibrocystic disease and breast cancer than it does to control goiter.

For people with breast cancer, daily dosages as high as 100 mg of iodine are often appropriate. Don’t do this without medical supervision. Discuss iodine supplementation with your doctor and monitor it regularly.

Dr. Abraham noted that iodine supplements have been taken for breast cancer in quantities as high as 6 grams a day without negative effects.