The average daily intake of iodine in the U.S. is 240 mcg, well
within the range that the International Council for the Control of
Iodine Deficiency Disorders defines as an optimal iodine intake,
150 to 299 mcg/day. Though considered ìiodine sufficient,î this
amount, 0.24 mg, is a small fraction of that consumed in Japan.
Also, this is half the amount of iodine that Americans consumed 30
years ago, when iodine was used more widely in the dairy industry
and as a dough conditioner in making bread. Now it is only added to
table salt, and 45 percent of American households buy salt without
iodine, which grocery stores also sell. And over the last 25 years
those who do use iodized table salt have decreased their
consumption of it by 65 percent. As a result, 15 percent of the U.S.
adult female population, one in seven, suffers from iodine
deficiency, as reflected in a urinary iodine concentration of less
than 50 mcg/L. One in seven American women now also develop
breast cancer during their lifetime (30 years ago it was 1 in 20).