Written by Patrick Massey, MD, PhD, Daily Herald Columnist. Iodine is used by humans in a number of biochemical reactions, most notably in the production of thyroid hormones.
Earlier this year, several nuclear reactors in Japan were compromised by a combination of a tsunami and earth quake. One result was a release of radioactive gas that had people in the US buying iodine to protect them from the effects of radiation. Buying iodine was unnecessary for this event but might be prudent because most Americans do not get enough in the diet.
Iodine is a relatively rare element, most concentrated in sea water…and even there is rare. Iodine is used by humans in a number of biochemical reactions, most notably in the production of thyroid hormones. Thyroid hormones are made in the thyroid gland. Thyroid hormones are directly involved with metabolism: too much hormone results in hyperthyroidism; too little and hypothyroidism occurs. There are several thyroid hormones made and may have 1-4 iodide atoms attached. The most common is T4 (4 atoms of iodine) while the most biologically active is T3.
Iodine is highly conserved by the human body because it is important and rare. The daily recommended dose is between 150 -250 micrograms. This is the dose needed to prevent the development of a goiter…enlarged thyroid gland, prevention of cretinism (extreme stupidity…maybe our politicians need some iodine) and hypothyroidism. However, iodine is used by many other tissues and the daily recommended amount for optimal health has not been defined.
The optimal amount of iodine is hard to determine because there is no accurate method of determining how much iodine is in the body. However, in Japan, kelp is a regular part of the traditional diet and goiter is almost unheard of because kelp contains a lot of iodine. They ingest 1-3 milligrams (4-12 xs the government recommended amount) of iodine without evidence of toxicity.
Why does it matter? Well, if iodine levels are low, you can feel tired, forgetful and unmotivated. Iodine is also important for heart function and brain function. It is also an old and effective medical therapy for fibrocystic breasts and may also reduce the risk of several cancers including breast cancer. Other elements common in our society can block iodine. Bromine blocks iodine and is carcinogenic. Chlorine also competes with iodine…and all of the municipal waters, pools and hot tubs contain chlorine (those of you who frequent hot tubs…definitely need iodine).
I believe that kelp is the best source of iodine. Most good health food and vitamin stores will have kelp. You want to take enough kelp to get 1 mg. That usually takes several tablets per day.
Posted October 29, 2011.
