The issue of iodine deficiency will be growing in importance over the coming decade. This is occurring for a number of reasons:
- Iodine deficiency with goiter has historically been widespread in the U.S. (especially in the Great Lakes region). This is why iodine was added to salt.
- Until recently, a lot of our iodine intake was from wheat (~ 25%).
- Unfortunately, flour mills have switched from adding iodine to using bromides instead. Bromides in flour was banned in the U.K. in 1990, and in Canada in 1994, as being toxic, but the FDA still allows its use in the U.S.
- As iodine and bromine (and fluorides) are all related chemically (called halides), they can act as competitive inhibitors to each other.
- Because of this, we are seeing iodine deficiencies from both decreased intake, and from bromine and fluorine making the iodine you do have less effective.
- Iodine intakes (estimated by urine output) dropped by ~ 50% from 1971 to 2001
- The current RDA for iodine is ~ 150 mcg/day. Much of this comes from iodine added to salt. Unfortunately, most of the salt used in food processing does not have iodine, and people are using less salt at home (the stuff that is iodized) because of the misguided medical advice (except in those with heart failure) to avoid salt. People who eat more salt live longer.
- An additional problem is that the addition of large amounts of unfermented soy (e.g., soy milk, soy cheese, soy protein added to food) inactivates an enzyme called "thyroid peroxidase" and can cause hypothyroidism. This is less of a problem with fermented soy products like tempeh and tofu.
What are the implications of iodine deficiency coming back?
- An epidemic of thyroid problems. Bromides which may block iodine function are implicated in many thyroid disorders (bromides are reported to be 50x higher in thyroid tissue of thyroid cancer patients). Low iodine can contribute to an increased risk of both an under or over active thyroid.
A key role that iodine plays is in breast tissue, and breast tissue from women with breast cancer have lower iodine levels than healthy controls. This effect is so marked, that hypothyroid women (who free up more iodine for breast tissue use) actually have lower levels of breast cancer. Women in Japan (who get much more iodine in their diet) have a 2/3 lower risk of breast cancer than women in the U.S.
It is probable that low iodine is a significant risk factor for breast cancer. One of the upcoming studies that our foundation is planning after we finish the Natural Therapy for Infertility Study is to add high-dose iodine to the therapy protocol of women with breast cancer.
Low iodine may increase the risk of heart disease. For a review of this issue, see Hypothesis: Dietary Iodine Intake in the Etiology of Cardiovascular Disease in the Journal of the American College of Nutrition.
Low iodine may also contribute to fatigue and CFS. A study showed that those with low body temperature and fatigue felt better on Iodine 1,500 mcg a day — even though their temperature did not rise with therapy. It is reasonable for those with chronic fatigue, CFS and fibromyalgia to try added iodine (Iodoral) for 3 months to see if it helps.
The accuracy of iodine testing has not been confirmed to my satisfaction, and I find that it often works best to address clinically based on your symptoms and then see if it helps. Much as we like to have a piece of paper that gives definitive results (lab and x-ray results), sadly these results are often not reliable (see Lab Testing is NOT Reliable!). I would simply address without doing testing in those who have:
- Breast cysts, tenderness, or cancer. I consider these markers for iodine deficiency.
- CFS or fibromyalgia.
- Thyroid disease or thyroid cancer.
- Low body temps (under 98.0 Fahrenheit). In one study using 1,500 mcg/day of iodine in those with fatigue and low temperature, the temperature did not come up, but the patients felt much better on it and had improved energy.
If you prefer to have lab confirmation, Dr. Kent Holtorf is using the urine iodine testing from Nitek and subsequent therapy with iodine when low. He estimates about 50-60% are low and about 20-30% very low. Dr. David Brownstein, a wonderful physician who wrote the book Iodine does an iodine loading test discussed in his book, which also shows ~ 95% of folks he tests to be low. The question with iodine testing is how one defines "low," and I personally am not anxious to do a test that does not affect how I address the issue with my patients.
Both simply addressing without testing or doing lab testing are reasonable options, and a good case could be made for helping everyone who has fibromyalgia or CFS, unexplained fatigue, or breast disease (cysts, cancer, or tenderness) with iodine for 3 months to see if they improve — without any testing.
We used to use Lugol's solution (a mix of iodine and iodide), but this is messy, irritating to the stomach, and can mildly stain teeth. A much-preferred option is to use iodine 12,500 mcg per day — a high dose. Some doctors are using 2-4 x times that dose a day, but these higher doses are best done under a holistic practitioner's supervision, as very high doses of iodine may suppress thyroid function. Though there is a concern about thyroid suppression from high iodine, this is generally not seen at a dose of 1 Iodoral a day (if you look at the actual studies as opposed to people simply speaking from no data). An additional benefit is that high dose Iodine may flush bromides out of the body over time, resulting in your being healthier and needing less Iodine over time.
- A small percent of those with Hashimoto's Thyroiditis will occasionally flare when taking iodine supplements (even in multivitamins). This usually goes away over time and the iodine is actually very helpful. Many who use high dose iodine, such as Iodoral, report that they see less sensitivity in these folks starting with a high dose of iodine instead of a low dose.
- In those with iodine allergies, I would not take the iodine supplement. Having said this, I have never seen anyone who had an allergic reaction to x-ray dyes also react to iodine supplements — but better safe than sorry.
Diet and Lifestyle
- Seafood tends to be higher in iodine. An especially rich iodine source is seaweed, such as kelp. This is why the average Japanese woman who eats a lot of seaweed gets 12,500 mcg of iodine in their daily diet, while in the U.S. most are lucky to barely get their 150 mcg a day. This may be why breast cancer and breast cysts are much less common in Japan than in the U.S. and England (the incidence of breast cancer is over 300% more common in the U.S. than Japan).
- Cut back on soy products if you eat a lot of them — especially unfermented soy.
- Consider using less fluoride (I prefer it be in toothpaste instead of drinking water) and Bromide (often found in hot tubs to keep down bacteria — other options are available).
Bottom Line? For those with CFS/FMS, unexplained fatigue, or breast symptoms, it is reasonable to take an iodine supplement for 90 days. After this, if you feel much better on it you can stay on it or stop to see if you still need it. You may find that taking it for 90 days is enough to "fill your tank" and correct any deficiencies, as a good multivitamin powder supplies 150 mcg a day (the full RDA) for maintenance. For those with breast cancer, I would add 12,500 mcg of iodine a day long term, and consider working with a holistic practitioner to take up to 5 a day while waiting for the research to be done.