You may have scrutinized the label of your prenatal vitamin to make sure it contains enough folic acid, calcium, and vitamin D. But what about iodine? It's estimated that only 20 percent of prenatal supplement brands contain the mineral—and this could be part of the reason why more pregnant and nursing moms in the US are iodine deficient, according to a Journal of the American Medical Association opinion paper that calls for iodine to be included in all prenatal vitamins.
The concern is being raised by researchers who say iodine levels among US women have steadily decreased over the past decade. Using statistics gathered by the US Centers for Disease Control and Prevention, researchers found that between 2001 and 2006, the average level of iodine among pregnant women was 150 micrograms, the lowest threshold for normal levels. Between 2007 and 2008, the median level among pregnant women was 129 micrograms per liter.
Why are iodine levels so important? The mineral is required for the production of thyroid hormone, and adequate thyroid hormone levels are critical for normal brain development in babies (low thyroid levels in moms can lead to problems that include fatigue, hair loss, and more). National and international health organizations currently recommend that pregnant women take at least 150 µg of potassium iodide daily.
How can you make sure you're getting enough? A good first step is to pay more attention to your diet. Iodine is most commonly found in dairy products, breads, seafood and sea vegetables (including kelp), write researchers. Iodized sea salt, eggs, onions, radishes, and watercress are some other food sources.
And then double check that your prenatal vitamin contains potassium iodide, which researchers consider the most stable source of iodine. It's also a good idea to run your need for iodine supplementation needs by your doctor, who can make specific recommendations and provide thyroid testing, if necessary.
"It's time for all healthcare professionals to make sure that every pregnant and breast-feeding woman gets supplemental iodine during pregnancy and while they are breast-feeding," recommends Dr. Alex Stagnaro-Green, professor of obstetrics and gynecology at the George Washington University School of Medicine and Health Sciences and lead author of the paper.
Stagnaro-Green says the solution to declining iodine levels is quite simple, "every prenatal vitamin in the US should have iodine supplementation."