Thursday, November 18, 2010
Wherefore Art Thou, Oh Iodine?
Recently my wife purchased a commercial Lugol's iodine solution: 5% of elemental iodine in a 10% solution of potassium iodide. This is a chemical preparation that has been made for a couple of hundred years. My guess is that each drop of a commercial 2.2% solution represents about 12.5 mg of iodine.
(I still need to do more research on this because too much iodine can cause thyrotoxicosis. It seems as though the symptoms of this are sort of "opposite" those of iodine deficiency so I think its unlikely the two could be confused.)
Commercial solutions must be less than 2.2% iodine lest they run afoul of government rules that limit certain substances that might be used in methamphetamine production. From what I can see this limit on iodine (at least iodine solutions) is nonsense as it relates to methamphetamine - supposedly its used to create HCl (using phosphorus, no less).
The Japanese consume iodine on the level of grams due to their seafood diets so it seems likely a few milligrams is not a concern.
This solution has changed her life dramatically in terms of energy, clearness of thought, and so on. This transformation was one I went through over the last five years or so (see "Five Years Ago..."). Again I am in "Flowers for Algernon".
So this transformation has left a question. Where has all the iodine that used to be added to our diets gone?
It turns out to be an interesting question with some interesting answers.
Prior to the early 1970's iodine supplementation in our diets had been in place since about 1924 or so when the Morton Salt Company introduced iodized salt. Similarly iodized salt was used in commercial baking.
I researching this I came upon a couple of articles. The first is a PDF here: "Bread Iodine Content and Thyroid Radioiodine Uptake: a Tale of Two Cities" This is an article written in a British NIH (National Institute of Health) publication in 1972. It seems to indicate that there is a problem with administering radioactive iodine thyroid tests if a patient is consuming iodine supplementation via baked goods.
Radioactive iodine tests are used to evaluate thyroid function. The patient ingests radioactive iodine and a scanner measures the radiation emitted by the thyroid in order to attempt to diagnose any problem (this is typically done if blood tests indicate a problem with thyroid hormones).
The second article "Normal Thyrodial Update of Iodine" (PDF here) talks about the regional variation in thyroid function as it relates to radio iodine uptake.
These articles seem to indicate two things: A) iodine absorption varies significantly by geographic location and B) too much iodine interferes with certain thyroid tests. Some internet posters claim this is the reason it was removed from baked goods as a supplement, but I don't think so.
Another article here indicates that "In 1948, Drs. Wolff and Chaikoff led a landmark study that determined that iodine can be harmful to the thyroid. While this is partially true, they were using only one part of the iodine element and not the whole mineral. If used correctly, iodine is very safe." The result of this was the reduction in the USDA daily Recommend Daily Allowance (RDA) of iodine to 150mcg.
This article indicates that 25mg (two drops of a lugol's solution - though no percentage is given) is good for two to three months to repair the bodies iodine deficiency and that, beyond that, 12.5 mg (one drop) is sufficient for maintenance).
Another article here shows that Australia, in 2008, believed that iodine deficiency was such a problem (though it does not indicate whether there ever was iodization or if there was why it was stopped and when) iodization of salt and/or other products should be introduced. Subsequent information seems to indirectly indicate that such a program has been implemented.
Then there is bromide. Bromide has been put into various food products as a replacement for iodine - bread in particular as well as flour.
Bromides affect some of the same receptors in the body that iodine affects. Bromide is not good for you. There is a long list of problems listed here - among them, not surprisingly, thyroid. A related theory is that if there is more bromide than iodine the bromide will "dominate" and cause problems. Related discussion revolves around detoxing from bromide before iodine will have its full effect as a supplement - but I am not certain I believe this.
Brazil has outlawed bromides.
So, why the banishment of iodine after all this?
My guess is cost and/or past medical incompetence.
I am think that not eating bread containing bromides would be good as well.