By Angela Lemond, RDN and Jessica MigalaMedically Reviewed by Kelly Kennedy, RD and Ross Radusky, MD
When many Americans hear the word iodine, they may think of salt. And that’s no surprise, since up to three-quarters of U.S. households use iodized salt to help boost the flavor of their food, according to previous research. (1) Indeed, most salt manufacturers have been participating in the voluntary program of adding iodine to table salt since the 1920s, to help correct iodine deficiencies, according to the National Institutes of Health (NIH). (2) Considering that many Americans eat too much salt, how can a person end up developing an iodine deficiency? The answer may surprise you.
What Is Iodine?
Iodine is a trace element that is found naturally in foods, is added to various foods, and is available in supplement form. It helps make our thyroid hormones thyroxine (T4) and triiodothyronine (T3), which play a role in protein manufacturing, the overall function of our metabolism, and the conversion to usable bodily substances, per the National Academy of Medicine, formerly called the Institute of Medicine. (3)
Benefits of Iodine
In utero and in infancy, iodine plays an important role in the development of your central nervous and skeletal systems.
(2) How much iodine breastfed babies receive depends on how much their moms take in. You can check the amount of iodine in your baby’s formula if he or she is formula-fed, but rest assured that the U.S. Food and Drug Administration (FDA) requires that infant formulas contain some iodine. (4)
Recommended Intake of Iodine
Iodine deficiency is most catastrophic to the developing brain. Therefore, requirements in pregnancy and lactation are much higher. (2) The Recommended Dietary Allowances (RDAs) for iodine are: (2)
Birth to 6 months: 110 micrograms (mcg)*7 to 12 months: 130 mcg*1 to 3 years: 90 mcg4 to 8 years: 90 mcg9 to 13 years: 120 mcg14 to 18 years: 150 mcg19 years and older: 150 mcgPregnancy: 220 mcgLactation: 290 mcg
*Adequate intake (AI)
RDAs are set to show the amount required to meet the needs of 97 to 98 percent of healthy people.
When there’s not strong enough evidence to show what the RDA is for a certain nutrient, AI is offered instead as an estimate for what amount of the nutrient, mineral, or element is enough. (5)