Iodine and The Thyroid — Worth A Second Glance

by Marcelle Pick, OB/GYN NP

  • Thyroid Iodine Second GlanceIodine deficiency — how common is it?
  • From intake to uptake — why are some of us so iodine deficient?
  • How’s your iodine? — iodine testing and treatment

We’ve all heard of iodine, of course. But if we were asked to define iodine’s role in human health, we might either think of it as merely an added ingredient to table salt (though many people don’t know why exactly), or as the bright orange tincture used by our parents to disinfect our childhood cuts and scrapes. But iodine is a critical element for healthy thyroid hormone production, and if it’s not available in the tiny amounts needed by the thyroid gland, there can be wide-ranging physical consequences.

These days, I have a growing concern that many of us may not be getting enough of this essential element. But although evidence of widespread iodine deficiency seems clear to me, the idea is still controversial in conventional medical circles. In a recent Newsweek article, an eminent medical school professor pronounced iodine deficiency to be rare in women in the US. Many of the magazine’s readers might not even give the subject a second thought. Yet compelling data were recently reported by the Centers for Disease Control suggesting that some 2.2 million women nationwide could have low iodine.

To learn more about the roles iodine, selenium, and other key nutrients play in thyroid function, see our article, “Simple Dietary Changes That Can Help Your Thyroid Naturally.”

Thyroid Iodine Second Glance Thoughtful WomanAs we learn more about how iodine functions in the body, research is revealing connections between diet, environment, and the rise of thyroid, breast, and immune health problems in women. Maybe you’ve had recent thyroid testing that came back borderline, or you’ve been diagnosed with hypothyroidism (inadequate production of thyroid hormones), and you’re already on thyroid medication. Perhaps you have fibrocystic breast condition and avoid salt by choice or due to high blood pressure. If so, it’s possible you could benefit from more insight into your iodine status and available testing and treatment options.

Iodine deficiency — how common is it?

As a practitioner of functional medicine, I am more and more intrigued by iodine. How widespread is iodine deficiency?  Why is it downplayed, and even overlooked here in the US?  When iodine deficiency was first recognized as a public concern in the 1920’s, iodine was subsequently added first to flour, then to salt, and the problem was considered solved.

In the US, it’s estimated that one in seven women suffers from iodine deficiency.

-Caldwell, K., et al. 2005; Hollowell, J., et al. 1998

But many people don’t know that flour isn’t iodized anymore, and iodization of salt is still voluntary in the US — only one-fifth of our salt is actually iodized. In reading further, I’ve found that we’re trending back toward iodine deficiency. Iodine intake has declined 50% in North America in the past 30–40 years, and this is consistent with what I’m seeing in my patients.

Thyroid Iodine Periodic Table SymbolAs recently as 2004, the New England Journal of Medicine defined our iodine status here in the US as “marginal,” based on data acquired from the International Council for the Control of Iodine Deficiency Disorder and the World Health Organization (WHO). More specifically, the WHO data suggest the greater risk in the US is not iodine deficiency per se, but iodine-induced hyperthyroidism (overproduction of thyroid hormones) or iodine-induced hypothyroidism. Interestingly, both these problems can occur when people who are already iodine-deficient are given too much iodine, too quickly. I believe practitioners need to proceed more cautiously when prescribing iodine supplements, slowly bringing levels up rather than overloading right up front. (More on our treatment protocol for iodine deficiency below).  But the WHO perspective seems to confirm that iodine deficiency does exist here in the US.

For more information about hypothyroidism, read our numerous articles on the topic in our Thyroid Health Category in our Health Library.

Thyroid Health Nutritional Supplement System