You’ve probably heard of iodine because you see the word “iodized” on your salt container. But you may not have thought much past that. However, If you’re pregnant or thinking about it, it’s vital that you get enough of this key nutrient for brain development.
Iodine deficiency in pregnancy is a worldwide problem and has become a global public health concern since it is identified as the leading cause of preventable brain damage in newborns and infants due to inadequate intake by mothers and infants.
Academy of Nutrition and Dietetics; www.eatright.org
Why It’s Important
Iodine is necessary for the body to make thyroid hormones. Not getting enough can cause serious issues such as hypothyroidism, an enlarged thyroid gland, (also called goiter) and weight gain. Why is it so critical during pregnancy, infancy and childhood? Because it’s necessary for brain development.
What If You Don’t Get Enough Iodine?
- Most importantly, iodine deficiency during pregnancy can cause irreversible brain damage in her infant.
- Not enough iodine during infancy and early childhood can cause lower IQ, reduced intellectual and motor performance and even an increased risk of ADHD.
- In adults, not getting enough iodine can cause impaired brain function. Also, iodine may have an impact on immune health and fibrocystic breast disease.
- Chronic iodine deficiency may be associated with an increased risk of the follicular form of thyroid cancer.
Are You Getting Enough Iodine?
You’re more likely to not get enough iodine if you:
- Eat a vegan or mostly plant-based diet.
- Avoid dairy foods.
- Avoid fish and seafood.
- Don’t eat much added salt.
More people are turning toward plant-centered diets (which is a good thing). But it also means some nutrients could be missing, becauase the main source of dietary iodine comes from dairy products and seafood.
How Much Do You Need?
- 1 to 8 years old: 90 micrograms
- 9 to 13 years old: 120 micrograms
- 14 years and older: 150 micrograms
- Pregnant: 220 micrograms
- Lactating: 290 micrograms
Where to Find It
| Food | Micrograms (mcg) per serving | Percent DV* |
|---|---|---|
| Bread, white, enriched, made with iodate dough conditioner, 2 slices** | 320 | 213 |
| Bread, whole-wheat, made with iodate dough conditioner, 2 slices** | 309 | 206 |
| Cod, baked, 3 ounces | 158 | 106 |
| Seaweed, nori, dried, 2 tablespoons, flaked (5 g) | 116 | 77 |
| Oysters, cooked, 3 ounces | 93 | 62 |
| Yogurt, Greek, plain, nonfat, ¾ cup | 87 | 58 |
| Milk, nonfat, 1 cup | 85 | 57 |
| Iodized table salt, ¼ teaspoon | 76 | 51 |
| Fish sticks, cooked, 3 ounces | 58 | 39 |
| Pasta, enriched, boiled in water with iodized salt, 1 cup | 38 | 25 |
| Ice cream, chocolate, ⅔ cup | 28 | 19 |
| Egg, hard boiled, 1 large | 26 | 17 |
| Cheese, cheddar, 1 ounce | 15 | 10 |
| Liver, beef, cooked, 3 ounces | 14 | 9 |
| Shrimp, cooked, 3 ounces | 13 | 9 |
| Tuna, canned in water, drained, 3 ounces | 7 | 5 |
| Fruit cocktail in light syrup, canned, ½ cup | 6 | 4 |
What If you Don’t Eat Any Iodine-Rich Foods?
You can either try to start eating them on a regular basis, or look for a multivitamin that contains iodine. This might be difficult as one study found that 25% of multivitamins don’t contain iodine. It’s even worse for prenatal vitamins because 40% were found to not include iodine. Look carefully at the label. If a vitamin contains 100% of the Daily Value, it means it contains 150 mcg.
What About Salt?
You should always buy iodized salt. However that doesn’t mean you’ll be getting all the iodine you need. One gram of salt (about 1/4 tsp.) has about 50 mg of iodine, 1/3 of the recommended daily intake for adults (and only 23% of pregnancy needs.) Though sea salt may contain extra minerals, it is likely to contain less iodine than iodized salt (and a pinch of plastic too!) We get a lot of our sodium from processed foods, but much of the salt used in industry is not iodized. So your best bet if you don’t eat a lot of salt or eat iodine rich foods is to choose your multivitamin or prenatal supplement very carefully.
References:
Iodine, A Critical Nutrient, Kathleeen Zelman MS, RDN, contributor, American Academy of Nutrition & Dietetics. www.eatright.org
Iodine: Health Professional Fact Sheet. National Institutes of Health. Updated April 2022.
Iodine Content is Low or Absent in US multivitamins and Prenatal brands. Clinical Thyroidology for the Public. May 2019. Vol 12 Issue 5 p.3-4. American Thyroid Association.
Q & A: Sea Salt and Sufficient Iodine Intake. Mayo Clinic.
