125 Iodine [1 August 2011]

Iodine is an essential trace mineral that has many functions besides its main role as a component of the thyroid hormones. Iodine is essential for proper brain development in infants and young children; deficiencies during pregnancy can result in severe intellectual disabilities, and may play a role in some ADHD cases. Iodine deficiency results in an enlarged thyroid gland, commonly called a goiter, but iodine is essential for the function of all the glands and hormones in the body, not just the thyroid. Iodine deficiency has been linked to breast cancer and possibly to ovarian and prostate cancers. It has been used to prevent and treat ovarian cysts and fibrocystic breast disease.

Iodized table salt is our main food source, and may be inadequate. We all are (or should be) reducing our salt intake, so are getting less iodine as well as sodium. Sea salt is low in iodine, and even iodized salt may not contain as much as we thought – a University of Texas study found half of 90 salt samples analyzed didn’t meet the FDA’s recommended level of iodine. Kelp is the richest natural food source of iodine, but is rarely on the menu in this country. That leaves supplementation to ensure that we are getting enough. Iodine is available as kelp tablets or capsules, and as a liquid supplement.

And how much iodine is enough? The Canadian RDA is 150 mcg (0.15 mg) for adults, less for children. Japanese who are among the healthiest people in the world (with low rates of breast, uterine and ovarian cancers) consume an average of 13.8 mg (nearly 100 times the Canadian RDA). Several studies have shown that to prevent and control fibrocystic breast disease, a minimum of 5 mg per 50kg (110 lb) body weight is required. David Brownstein, author of the book “Iodine – Why You Need It, Why You Can’t Live Without It”, found 96% of 4,000 Americans tested to be deficient in iodine. Maybe they were following the Canadian RDA?

This article is intended for educational purposes only; for medical advice consult your licensed health practitioner.