Do You Need Iodine?
Many decades ago, iodization of salt was voluntarily instituted in the U.S. and other industrialized countries as a means to counteract iodine deficiency. In these areas with iodized salt, iodine deficiency disorders were all but eliminated, and most Americans do have sufficient iodine.During the past two decades, however, reductions in salt intake for health reasons, reduced use of iodized salt in processed foods, and the fact that iodization is not mandatory in the U.S. (even then, some 70% of table salt is iodized) have resulted in a cutback in iodine intake even in countries like the U.S. So after a period where iodine deficiency in the U.S. had been all but eliminated, it is now on a slow by steady upward rise.
The greatest concern is in pregnancy women. In fact, the rate of pregnant women with iodine deficiency has increased in the U.S. over the past 20 years Utiger, from just 1 percent in the 1970s to 7 percent in 2002. These women and their babies face the greatest risks from insufficient iodine in their diet.
Some experts recommend that iodine supplementation be standard during pre-conception and pregnancy. The recommended dietary allowance for iodine is 200 mg/day during pregnancy and 75 mg/day while breastfeeding.
For the rest of us, the answer for optimum thyroid health is, therefore, to get enough -- but not too much -- iodine. You might be deficient in iodine if you have, for health reasons, cut iodized salt out of your diet, or switched to non-iodized sea salt.
So, do you need supplemental iodine? How can you tell for sure if you are getting enough iodine? It's almost impossible to gauge on your own. You can do an very rough estimate, however, based on the following questions:
- Do you use iodized salt?
- How much salt do you eat daily?
- Do you take a vitamin or supplement with iodine? (How much iodine is in the supplement?)
- Do you eat, meat, dairy products or seafood regularly?
But, unless you are planning to get pregnant, are currently pregnant or you're breastfeeding, you'll want to be very careful about taking iodine unless you and your practitioner have some very strong evidence that you are deficient. If your practitioner recommends iodine supplementation as a thyroid treatment, you may wish to ask for a more specific test that can measure iodine levels -- the "urinary excretion" test. This test which evaluates the iodine excreted in the urine, and gives an indirect but fairly accurate assessment of iodine levels, and can document deficiency.
Also, watch out for the so-called "thyroid support" vitamin and supplement formulas, including the heavily marketed and promoted Alvidar. Most, like Alvidar, include substantial amounts of iodine, and if you are not iodine-deficient, they can end up having the unintended and opposite effect of actually making your symptoms worse, and aggravating your thyroid condition.
SOURCES:
Teng, Weiping M.D., et. al. "Effect of Iodine Intake on Thyroid Diseases in China" New England Journal of Medicine, Volume 354:2783-2793, June 29, 2006, Number 26Utiger, Robert D. M.D. "Iodine Nutrition — More Is Better," New England Journal of Medicine, Volume 354:2819-2821, June 29, 2006, Number 26
Higdon, Jane Ph.D. et. al. "Iodine," Micronutrient Information Center, Linus Pauling Insitute, Oregon State University, 2003 Article
International Council for the Control of Iodine Deficiency Disorders
Shomon, Mary J. Living Well With Hypothyroidism: What Your Doctor Doesn't Tell You...That You Need to Know, HarperCollins, 2005
Shomon, Mary J. The Thyroid Guide to Fertility, Pregnancy and Breastfeeding Success, Thyroid-Info, 2006
