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).
Creswell Eastman
His preferred method of delivery for pregnant and lactating women is via oral iodine supplements. In his day to day practice at the Sydney Thyroid Clinic he will give priority to pregnant women. Eastman's work in China indicates that adequate iodine intake has resulted in an overall increase in the national IQ. He is of the opinion that recent testing of children in Australia that showed a decline in results in Australian children may be caused by iodine deficiency. This was a problem that he previously flagged in 2007: "If we don't address this in Australia then we are likely to see a lot of children born in coming years that have lower IQs, have problems with hearing, have great learning difficulties and they are less likely to fulfill their genetic potential."Eastman is married to Annette, whom he met while a medical student, and has four children Katherine (Kate), born 1966; Damien, born 1968; Phillipa, born 1970 and Nicholas, born 1974.