Iodine in biology
The U.S. Institute of Medicine (IOM) updated Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for iodine in 2000. For people age 14 and up, the iodine RDA is 150 μg/day; the RDA for pregnant women is 220 μg/day and the RDA during lactation is 290 μg/day. For children 1–8 years, the RDA is 90 μg/day; for children 8–13 years, 130 μg/day. As a safety consideration, the IOM sets tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. The UL for iodine for adults is 1,100 μg/day. This UL was assessed by analyzing the effect of supplementation on thyroid-stimulating hormone. Collectively, the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes (DRIs).
Nascent iodine (dietary supplement)
The diatomic form of elemental iodine I2, has no electrical charge. Monoatomic iodine also has no electrical charge, but is unstable and highly reactive (free radical, labeled as an I with a dot, I* ). It can be produced by exposing I2 to ultraviolet light. Electric and magnetic fields won't do it, as is sometimes incorrectly suggested.I should mention a few points about Edgar Cayce's atomidine. This famous visionary wrote several articles about the best form of iodine supplement (18). Some claim that this was iodine trichloride, but that cannot be true as this compound is toxic by ingestion and damaging to mucous membranes. It decomposes to ICl and poisonous gas Cl2 at 77 degrees C and also in water at room temperature (19). Most likely Cayce's atomidine was simply a 1% iodine solution (I2) in 95% ethanol. I am surprised that there are educated people, even medical doctors who claim that "elemental monoatomic iodine" preparations (Atomidine, Nascent Iodine etc.) are the best forms of iodine supplements. May be it has something to do with efficient marketing? Elemental Iodine (I2) is soluble in glycerin. Replacement of ethanol with glycerol indeed makes these supplements more consumption-friendly, so they are sold by some vendors as superior products to Cayce's ethanol-formulated one. Personally, I think glycerol-based I2 supplements are inferior to iodides; however, they are excellent antiseptics.The best and safest form of iodine supplementation for a healthy adult is iodide. Iodides are naturally produced in larger quantities by various seaweeds.