I have used iodine to check my thyroid and also clear iodine for toenail fungus. My Naturopath suggested that I use the brown iodine and put a half dollar size circle on my abdomen every morning as long as it disappeared and the first morning it remained visible, stop the treatment. I do this every six months to keep my thyroid healthy.
For a really insightful viewpoint on iodine, check out this lecture by Dr. David Brownstein (http://www.internetwks.com/clips/bsBCancer.rm) about iodine and its deficiency relationship to Breast Cancer. Note he also suspects an unproven relationship between an iodine deficiency and Prostate Cancer.
He mentions that the Japanese diet includes 14mg per day of iodine on the average (coastal Japanese ingest even more.) The US RDA is 150 ugs (micro grams) per day -- about 100 times less than the Japanese eat -- and the recommended upper level for iodine is no more than 1.1 mg/day, and they estimate the average requirement to be 95 micrograms per day or about 150 times less than the Japanese consume.
The 125mg Kelp tablets that I have from Vitamin Shoppe, have 225 ugs of iodine in them. Thus, to get to the Japanese level of Iodine (14 mg/day), I would have to take 62 of these tablets a day! Dr. Brownstein also states that iodine is stored in the thyroid which requires 6 mg/day and is also stored in a women's breasts and required for proper breast development. The breasts require 5 mg/day for a 110 lb woman.
And catch this... Breast cancer researchers have to starve test animals of iodine in order to be able to induce breast cancer in any significant number of them. Hmmm...
Another 2 mg/day of iodine is required by the adrenals, hypothalamus, pituitary, and other organs. Therefore, the total required iodine for a woman is 5 6 2 = 13 mg/day. The RDA is 150 ugs per day, so a woman would have to take 86 times as much as this to achieve the 13 mg/day needed by her body, and even more if she had a larger body or bigger breasts. A man has smaller breasts and his prostate requires somewhat less iodine than a woman's breasts. However, a man's body is generally larger than 110 lbs, so this would have to be factored into the total requirements for a man.
Dr. Brownstein states, "Over the last 30 years, iodine levels have fallen over 50% in the United States. Breast cancer rates have risen dramatically. Thyroid illness from hypothyroidism, autoimmune including Grave's and Hashimoto's, as well as thyroid cancer has risen dramatically."
Since the Japanese have so much iodine in their bodies (they're ingesting 100X our 150 ug RDA of iodine), and iodine is essential for dealing with radiation exposure, it makes me wonder what might happen happen if there were a mishap involving massive radiation exposure in a country such as ours where the iodine level is so pathetically low.
And this may well be an important consideration, as cancer rates have been shown to rise after radiation has been released into the atmosphere, which apparently happened quite a bit with the use of depleted uranium (DU) weapons in Iraq in 2003. Background radiation levels were measured at many times normal in England (click this link - http://www.llrc.org/aldermastrept.pdf - and check the graphs) just a few days after the fighting started in Iraq. Cancer rates in Iraq in 2001 were about 10X what they were before Desert Storm where much less DU was used than in 2003. The big problem is that the effects are global (see: http://www.mindfully.org/Nucs/2006/DU-Europe-Moret26feb06.htm). So, the problem for us is that the DU rounds burn up or pulverize and tend to stay in the atmosphere, allowing the "aerosol of sub micron" size to enter the slip-stream and come back to America to bite us all.
Therefore, we all need to be aware of any nutritional and purification techniques which will handle radiation.
I've just upped my iodine intake to 1.35 mg/day (6 kelp tablets of 225 ug each) and I feel warmer already (maybe this will help me burn off my excess fat even faster.)