Iodine in biology
The U.S. Food and Nutrition Board and Institute of Medicine recommended daily allowance of iodine ranges from 150 micrograms per day for adult humans to 290 micrograms per day for lactating mothers. However, the thyroid gland needs no more than 70 micrograms per day to synthesize the requisite daily amounts of T4 and T3. The higher recommended daily allowance levels of iodine seem necessary for optimal function of a number of other body systems, including lactating breasts, gastric mucosa, salivary glands, oral mucosa, arterial walls, thymus, epidermis, choroid plexus and cerebrospinal fluid, among others.
Ethylenediamine dihydroiodide
EDDI is used as an additive in pet food and cattle feed with high bioavailability. Used to prevent iodine deficiency, this salt is one of the major uses of the element iodine. The United States Food and Drug Administration suggests a limit of intake to 50 mg/head/day. Although EDDI is generally recognized as safe (GRAS) only as a nutrient source of iodine, administration of EDDI also has preventative effects on foot rot in cattle.