Iodine

Iodine is a vital component of thyroid hormones thyroxine (T4) and triiodothyronine (T3). The mother’s thyroid hormone levels affect proper fetal growth and neurological development during pregnancy and after birth.
Who is at risk for iodine deficiency while breastfeeding?
- Women who do not regularly consume dairy products or seafood.
- Women who smoke cigarettes.
- Women who do not use iodized salt.
- Women who eat foods containing goitrogens, which are substances that can affect how well
the thyroid gland makes thyroid hormones. These foods include brussel sprouts, kale, cabbage, cauliflower, radishes, and broccoli.
Do infants get enough iodine from breast milk?

Usually. The recommended dietary allowance (RDA) (the average amount of a vitamin or mineral that meets the daily nutrient needs of nearly all healthy people) of iodine is higher for women when they are pregnant or breastfeeding in order to support proper fetal or infant growth and neurological development. Although breast milk contains iodine, concentrations can vary based on maternal iodine levels. If a pregnant or breastfeeding woman is deficient in iodine, the fetus or infant may be at risk for iodine deficiency and associated cognitive and psychomotor impairments.
Period | Iodine RDA |
---|---|
Before Pregnancy | 150 µg per day |
During Pregnancy | 220 µg per day |
Breastfeeding | 290 µg per day |
Because the diet of a pregnant or breastfeeding woman may not contain enough iodine to meet the RDA, the American Thyroid Associationexternal icon and the American Academy of Pediatricsexternal icon recommend that pregnant or breastfeeding women take a daily multivitamin or prenatal supplement every day containing 150 µg of iodine.
Not all multivitamin and prenatal supplements contain 150 µg of iodine; therefore, all women should check the nutrition label or speak with their health care provider about whether their multivitamin supplement or prenatal vitamin contains enough iodine.
- Iodine Fact Sheet for Health Professionalsexternal icon – National Institutes of Health
- Iodine Fact Sheet for Consumersexternal icon – National Institutes of Health
- Iodine Supplementation for Pregnancy and Lactation-U.S. and Canada: Recommendations of the American Thyroid Association pdf icon[PDF-54KB]external icon
- Iodine Deficiency, Pollutant Chemicals, and the Thyroid: New Information on an Old Problemexternal icon – American Academy of Pediatrics
- Recommendations on Iodine Nutrition During Pregnancy and Lactationexternal icon – American Academy of Pediatrics
- Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2001external icon – National Academy of Medicine