Under the supervision of Prof. Aron Troen and Dr. Dov Gefel
PhD thesis final lecture abstract:
Background: adequate iodine intake is essential for thyroid function and human health throughout life. Iodine deficiency (ID) impairs human health and function via diverse disorders, collectively named ID disorder (IDD). These disorders also include goiter (at all ages) and impaired intellectual potential (in children) even in mild ID areas. ID is estimated to affect about third of the world's population and recently has re-emerged in many industrialized countries, even those performing national iodization programs; however, national data on iodine status in Israel is lacking, although reports on endemic goiter along with low iodine concentration of water sources in the north of the country during previous century. Nowadays, Israelis are reliant on iodine-depleted desalinated water, absent with any iodization program and report of increased use of thyroid medication. Our preliminary findings included local association between low iodine intake and goiter as well as elevated serum thyroglobulin (Tg) values among euthyroid adults exposed to iodine-diluted desalinated water.
Overall aim: to create an evidence base for iodine policy in Israel and elsewhere; Findings: A) A novel evidence of prevalent probable IDD in a population reliant on desalinated seawater; B) Mild ID in a national geographic-representative sample of school aged children and iodine insufficiency in a nationally-representative sample of pregnant women by urine sampling via efficient and cost-saving method using a centralized national laboratory; C) Israeli milk and dairy products are iodine rich, but it is unlikely that population sufficiency can be reached from diet alone without salt iodization.
Conclusions: Israel is an ID area and it population is at risk of IDD. Our findings implies that it is likely that Israeli children are achieving suboptimal intellectual potential mainly due to mild ID and Israeli women are at risk of developing goiter. The evidence of heavy national reliance on desalinated water in Israel, together with low iodine intake from milk and dairy products among its population, indicate that new causes might be involved in the old global public health concern of ID and therefore IDD. Trends of increased use of desalinated water elsewhere, along with the apparent decline in milk and dairy products consumption (per capita) in industrialized countries, highlights the need of implementation and adjustments of iodine prophylaxis as well as frequent and routine monitoring of iodine status in the public.