Before we delve into the top iodine foods that help maintain thyroid function, let’s first take a closer look at what exactly iodine is, how it benefits your health, and how much you need on a daily basis.
What is iodine?
“Iodine is a trace mineral found in some foods and added to others. It is also available as a dietary supplement,” says Dr Nisha Jayania board-certified endocrinologist with pigeon health. Iodine does not occur naturally in the body, which means that it is essential that we obtain it through dietary sources.
“Iodine is necessary for the thyroid gland to produce the thyroid hormones T4 and T3,” says Dr. Jayani. “The pituitary gland in the brain releases thyroid-stimulating hormone (TSH) when it detects that the thyroid hormones T4 and T3 are low. The cells of the thyroid gland produce T4 and T3 by combining iodine and tyrosine, an amino acid. Once T4 and T3 are created, these hormones are distributed throughout the body to regulate metabolism as well as support other vital functions as noted above.
Again, iodine is a key player when it comes to thyroid health: Dr. Jayani explains that the cells of the thyroid gland are the only cells in the entire body that absorb this nutrient. “Without iodine, the thyroid gland can’t make T4 and T3,” he reiterates, and a lack of these hormones can ultimately lead to hypothyroidism (also known as an underactive thyroid). Weather symptoms of hypothyroidism can vary from person to person, the most common include fatigue, lethargy, constipation, feeling cold and dry skin.
How much iodine do you need?
“The Recommended Dietary Allowance (RDA) for iodine is about 150 mcg for adult men and women, and about 100 mcg more for pregnant and lactating women,” he shares. Jennifer Maeng, MS, RD, LD, CDN, CNSCregistered dietitian and founder of Chelsea Nutrition.
To inch closer to this RDA for supporting thyroid function and thus your mood, energy levels, metabolism, and more, consider stocking up on Maeng’s approved list of iodine-rich foods below. Also, keep in mind that, according to the National Institutes of Health, the the tolerable upper intake level (UL) for iodine is 1,100 mcg for all adults.
The best foods with iodine, according to the recommendations of a dietician
1. Algae
While seaweed is an excellent source of iodine, Maeng notes that the exact amount of this all-important mineral varies depending on the type or specialty of seaweed you’re cooking with. kombu seaweed, which she says is “most commonly used to make Japanese soups,” contains the highest amount of iodine at nearly 3,000 mcg per gram. Note that this is well above the RDA for iodine.
2. Cod
“Cod contains between 65 and 100 mcg of iodine per three ounces,” says Maeng. While he explains that the iodine content of cod varies depending on a variety of factors, including the region in which it was caught, whether the fish was wild-caught or farm-raised, and its fat content, cod is still a excellent option to load up on this essential mineral (as well as other types of lean fish and shellfish).
3. Dairy
You’re in luck if you start your morning with probiotic-rich yogurt (or always work on your nightly cheese a la Liz Lemon), as Maeng mentions, dairy is the largest source of iodine in the standard American diet. That said, the total iodine content in dairy varies across different food sources and their respective fat content. “Per cup, milk can contain 60 to 115 percent of the RDA for iodine, while plain yogurt contains about 50 percent,” says Maeng. From there, she says the iodine content in cheese varies more significantly, although cottage cheese contains more than 65 mcg per cup.
4. Iodized salt
According to the Centers for Disease Control (CDC), most Americans have too much sodium in their diets, registering an average of 3400 mcg, while in reality we should reach a maximum of 2300 mcg. While most of this intake typically comes from processed and prepared foods, if you’re going to add salt to your meals, try to prioritize iodized salt when possible. “A quarter teaspoon of iodized salt contains about 70 mcg of iodine,” says Maeng, which is almost half of the RDA for this micronutrient. Since excess salt and sodium are linked to several harmful health conditions, he recommends being careful when sprinkling foods and not overdoing it for the sole purpose of increasing iodine intake.
5. Shrimp
“Shrimp are a good source of iodine because, like other fish, they can absorb the iodine naturally found in seawater,” says Maeng. A three-ounce serving of shrimp will contain about 35 mcg of iodine, in addition to other essential nutrients like selenium, phosphorus and vitamin B12, she adds.
6. Eggs
Whether you prefer your eggs scrambled, boiled, poached, or otherwise prepared, you’ll be pleased to know that they’re a decent source of iodine at around 25 mcg each. However, egg white omelettes won’t have the same impact, since “most of this iodine comes from the yolk,” says Maeng.
7. prunes
While prunes are known to be an excellent source of fiber, Maeng also says that they are a good vegan source of iodine. (In other words, these nuts come in handy especially for plant-based eaters as well as people who are endorsed). “Five prunes contain about 15 mcg of iodine, and they also contain a lot of iron, vitamin K, vitamin A, and potassium,” says Maeng.
