Iodine is a trace mineral commonly found in seafood. It is an essential micronutrient, which means your body needs it to function properly. By itself, iodine is a dark, glossy stone or a purple pigment. However, it is usually found in invisible trace amounts in water and soil or as part of other food compounds.
Your body uses iodine to run various important processes in the body. Although iodine supplements are found, iodine is frequently added to other foods as a fortifier. Where iodine is inaccessible, iodine deficiency is rare. However, about one-third of the world is still at risk of iodine deficiency. Getting enough iodine in your diet helps improve your metabolism, your brain health, and your hormone levels.
Iodine Rich Foods
Iodine can be found in a number of foods, but it’s most common in seafood. Eating a diet rich in fish can help you get enough iodine to experience the benefits it offers. According to the National Institutes of Health, these eight foods are some of the best sources of iodine available.
Seaweed
Hands down, seaweed is the best source of iodine available. A 10 gram serving of dried nori seaweed (the type of seaweed used in sushi) contains up to 232 mcg of iodine, more than 1.5 times the daily required minimum.
Cod
Seafood, in general, is a great source of iodine, but cod is particularly healthy. A three-ounce serving of baked cod contains 158 mcg of iodine, which meets your daily minimum.
Iodized Salt
Salt or table salt for human food use to which iodide has not been added shall bear the statement, “This salt does not supply iodide, a necessary nutrient.”
Nonfat Milk
Aside from seafood, dairy is one of the best iodine options available. An eight-ounce serving of nonfat cow’s milk contains 85 mcg of iodine, more than half of what you need daily.
Greek Yogurt
Like milk, nonfat Greek yogurt is an excellent source of iodine. Because Greek yogurt is denser than milk, it has a higher concentration of iodine: up to 116 mcg per eight ounces.
Oysters
Another great source of seafood iodine comes from oysters. Just three ounces of cooked oysters can provide up to 93 mcg of iodine, nearly two-thirds of what you need per day.
Eggs
Animal sources of iodine are generally the richest sources available, and eggs are no exception. A single hard-boiled egg provides about 26 mcg of iodine.
Enriched Bread
While bread on its own is rarely high in iodine, some manufacturers make it with an “iodate dough conditioner.” These conditioners are added to enrich the bread, as with table salt. A single slice of white bread made with an iodate dough conditioner contains up to 185 mcg of iodine.
Liver
There are few foods that are as nutritionally dense as beef liver. A three-ounce serving of liver can provide 14 mcg of iodine along with the many other vitamins and nutrients it contains.
Halibut
Halibut is another seafood high in iodine. Research shows that Atlantic halibut contains about 21 mcg of iodine per serving. Although that is less than some other fish, it still provides a good amount of iodine.
Pollock
Pollock is a member of the cod family that frequents the cold waters of the North Pacific. A 120 gram (g) serving of Alaskan pollock provides around 67 mcg of iodine, which is about half of the RDI. It also contains omega-3 fatty acids, phosphorus, selenium, and niacin, which all contribute to immune and nervous system health.
Crab
Though crab contains less iodine than other seafood, it still provides 26–50 mcg in a 100-g serving. Besides being a good source of protein, crab also contains many other essential nutrients. It provides selenium, B12, and zinc.
Scallops
Scallops are a great source of iodine. They provide 135 mcg per serving, which is 90% of the RDI. They may also be beneficial for heart health and the central nervous system.
Squid
Squid, commonly consumed as calamari, contains about 65 mcg per serving. It is also a good source of Vitamin C, iron, calcium, and omega-3 fatty acids.
Tuna
Because tuna is a fattier fish than other varieties, it contains less iodine. However, at 17 mcg per 3 oz. serving, it is still a decent source of the mineral. Tuna is an accessible, relatively affordable source of iodine that people may find easier to add to their diet than some other seafood.
Cheese
Certain types of cheese provide more iodine than others. However, on average, cheese contains 37.5 mcg of iodine per 100 g of cheese.
Iodine can be found in a number of foods, but it’s most common in seafood. Eating a diet rich in fish can help you get enough iodine to experience the benefits it offers. According to the National Institutes of Health, these eight foods are some of the best sources of iodine available.
How Much Iodine Per Day?
According to the National Institutes of Health (NIH), the recommended daily intake for iodine is 150 mcg in adult men and women. In the United States and Canada, just one teaspoon of iodized salt contains 250 mcg. This makes it relatively easy to meet the RDI. It is important to note the iodine recommendation for pregnant females is significantly higher, at 220 mcg.
Because the risk of iodine deficiency drastically increases during pregnancy, the American Thyroid Association recommends that people planning on becoming pregnant take a daily prenatal vitamin containing at least 150 mcg of iodine.
Why You Need Iodine
Your body can’t produce iodine, which makes it an essential micronutrient. Iodine is critical for your thyroid and plays an important role in the production of thyroid hormones.
Since your body can’t produce iodine, it’s important to get enough from your diet. The currently accepted minimum daily intake requirement for iodine is 150 micrograms (mcg). Pregnant and lactating women should consume 220 and 290 mcg respectively.
If you aren’t getting enough iodine, you may start to develop symptoms of hypothyroidism or begin to develop a goiter (abnormal enlargement of your thyroid gland).
Iodine Health Benefits
Prevents Hypothyroidism
Hypothyroidism is a condition that occurs when your body cannot produce enough thyroid hormone. This hormone helps your body maintain its metabolism and supports your organ function. Iodine is critical for your body’s thyroid hormone production, so getting enough iodine may prevent or cure symptoms of hypothyroidism.
Prevents Goiters
If your body is unable to produce enough thyroid hormone, then your thyroid itself may start to grow. Your thyroid is in your neck, just under your jaw. When it starts to grow, you will notice a strange lump developing on your neck. This is known as a goiter. Getting enough iodine can prevent goiters.
Reduced Risk of Birth Defects
People who are pregnant should consume more iodine than others. Iodine helps prevent several types of birth defects. In particular, iodine helps support healthy brain development. Getting enough iodine during pregnancy can prevent birth defects that affect the brain, miscarriage, and stillbirth.
Risks of Too Much Iodine
Consuming too much iodine can also be problematic. A diet containing excess iodine is associated with thyroid gland inflammation and thyroid cancer. The damage from a high-iodine diet occurs over time.
Additionally, eating a very large serving of iodine at one time can result in short-term discomfort. A person may experience burning of the mouth and stomach, fever, nausea, and diarrhea.
People who take iodine supplements should ensure the product contains only the RDI, or less, in order to avoid consuming too much iodine.