Dotting the I 

Colorful bindis are being handed out to tribal women in India by a philanthropic organization. When worn on the forehead, each dot delivers a daily dose of 100-150 micrograms of iodine (chemical symbol: I) which is absorbed by the skin. At least 70 million Indians suffer from iodine deficiency disorders. Sure, oral supplements or iodized salts are more efficient, but the tribal women won't take them. The bindis are a socially more acceptable, and creative, approach to dietary compliance! 

Bad Air: Iodine deficiencies were described by ancient Roman writers and medieval travelers, who would encounter entire villages in the Alps or southern Europe struck by cretinism.  Thought to be due to "bad air" or "stagnant water" in the mountains, we now know that dwarfism, deformed bones and intellectual disability are due to lack of iodine-rich thyroid hormone. Goiter belts characterized the more mildly afflicted inland regions of Europe and N. America, where populations were marked by enlarged thyroids and grossly swollen throats. Along the coast, however, wave action disperses natural iodine salts from sea water into the air, from where it enters our ecosystem. No wonder, sea air was recommended for recuperating invalids. 

The Rise and Fall of I: After the discovery of iodine in 1811, Lugol's solution (mostly potassium iodide, or KI) became the universal panacea of western medicine. Medical students were advised:

If ye don’t know where, what, and why 
Prescribe ye then K and I

But too much of a good thing led to the discovery that excess iodine actually blocked thyroid hormone production (known as Wolff-Chaikoff effect). Today, the Reference Daily Intake or RDI has decreased from 1 gram, to 150 micrograms, which many practitioners believe is too little. Proponents of iodine therapy point out the benefits in preventing breast cancer, skin disorders and more. For a fascinating history of the controversies and facts see the article in the reference. 

REF: http://www.westonaprice.org/modern-diseases/the-great-iodine-debate/

Video: Jeevan Bindi- The Life Saving Dot (1 min long)
https://youtu.be/Sclg_AfGzcE

Photo: Subir Basak 
https://www.flickr.com/photos/subirbasak/

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