Iodine is a trace mineral found in some foods. It’s an essential micronutrient, which means that your body needs it to work properly. It’s generally found in small amounts in water and soil, or as part of other compounds in food.
Getting enough iodine in your diet has been shown to help improve your metabolism, brain health, and hormone levels.
Why You Need Iodine
Your body can’t make iodine, but it’s necessary for your thyroid. It plays an important role in the production of thyroid hormones.
Your body can’t make iodine on its own, so you need to get enough from your diet. Most adults need at least 150 micrograms of iodine each day. Pregnant and breastfeeding parents should get 220 and 290 micrograms, respectively.
Getting enough iodine has been shown to help your body in many ways, including:
Preventing hypothyroidism. Hypothyroidism is a condition that happens when your body cannot make enough thyroid hormones. These hormones help your body’s metabolism and support your organ function. Getting enough iodine may prevent or help symptoms of hypothyroidism.
Preventing goiters. If your body is unable to make enough thyroid hormones, your thyroid gland may start to grow. The thyroid is located in your neck, just under your jaw. When it starts to grow, you may notice a lump on your neck. This is known as a goiter. Getting enough iodine can prevent goiter.
Reduced risk of birth defects. People who are pregnant should get 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 issues such as:
- Brain damage
- Conditions present at birth (congenital conditions)
- Miscarriage
- Stillbirth
Signs and symptoms of iodine deficiency
Your body uses iodine to run several important processes. While iodine supplements are available, iodine is also added to other foods. In places where iodine fortification is common, iodine deficiency is rare. But around the world, nearly 1 in 3 people are at risk for iodine deficiency.
If you have iodine deficiency, you may not have symptoms at all. But if they do show up, they may include symptoms of hypothyroidism, including:
- Constipation
- Depression
- Dry skin
- Feeling very tired
- High blood pressure
- Slow or weak heartbeat
- Weight gain
9 Foods Rich in Iodine
Iodine can be found in several foods, but it’s most common in seafood. Eating a diet rich in fish can help you get enough iodine. These foods are some of the best sources of iodine available.
1. Seaweed
Hands down, seaweed is the best source of iodine available. A 5-gram serving of dried nori (the type of seaweed used in sushi) has up to 116 micrograms of iodine. Wakame, kelp, and kombu are also rich in iodine.
2. Cod
Seafood in general is a great source of iodine, but cod is particularly nutritious. A 3-ounce serving of baked cod has 146 micrograms of iodine, which meets your daily minimum requirement.
3. Iodized salt
A quarter teaspoon of iodized table salt has about 78 micrograms of iodine. You can find iodized salt at most grocery stores.
4. Milk
Aside from seaweed, dairy is one of the best iodine options available. For example, an 8-ounce serving of milk contains 84 micrograms of iodine, more than half of what you need daily.
5. Greek yogurt
Like milk, Greek yogurt is an excellent source of iodine. Because Greek yogurt is denser than milk, it has a higher concentration of iodine: up to 87 micrograms per 3/4 cup.
6. Oysters
Another great source of iodine comes from oysters. Just 3 ounces of cooked oysters can provide up to 93 micrograms of iodine, nearly two-thirds of what you need per day.
7. Eggs
A single hard-boiled egg provides about 31 micrograms of iodine.
8. Enriched bread
While bread on its own is rarely high in iodine, some makers add “iodate dough conditioner” to enrich it with iodine, much like iodized table salt. Two slices of white bread made with an iodate dough conditioner can offer up to 296 micrograms of iodine.
9. Liver
Few foods are as nutritionally dense as beef liver. A 3-ounce serving of liver can provide 14 micrograms of iodine, along with many other vitamins and nutrients.
How These Iodine-Rich Foods Compare
The table below shows how these iodine-rich foods compare in terms of serving size, iodine content, and how much of your daily iodine needs they help meet.
| Food Source | Serving Size | Iodine Content | % Daily Value |
| Enriched bread | 2 slices | 296 micrograms | 197% |
| Cod, baked | 3 ounces | 146 micrograms | 97% |
| Seaweed (nori) | 5 grams | 116 micrograms | 77% |
| Oysters, cooked | 3 ounces | 93 micrograms | 62% |
| Greek yogurt | 3/4 cup | 87 micrograms | 58% |
| Milk | 1 cup | 84 micrograms | 56% |
| Iodized salt | 1/4 teaspoon | 78 micrograms | 52% |
| Egg, hard-boiled | 1 egg | 31 micrograms | 21% |
| Beef liver, cooked | 3 ounces | 14 micrograms | 9% |
Takeaways
Iodine is a trace mineral and essential micronutrient found in some foods. Your body needs iodine to work properly. Getting enough iodine in your diet may help boost your metabolism and your brain health. Foods that are rich in iodine include:
- Seaweed, including kelp, nori, kombu, and wakame
- Seafood, such as oysters and cod
- Enriched food, such as bread or iodized salt
- Dairy products, such as milk and Greek yogurt
FAQs About Foods High in Iodine
Here are some commonly asked questions about iodine and foods high in iodine.
Does sea salt or Himalayan salt have iodine?
The only salt with enough iodine is table salt or iodized salt.
Can cooking or boiling food destroy its iodine content?
Yes, cooking methods can affect a food’s iodine content. The amount of iodine lost during cooking depends on what cooking method you use and if you use salt while cooking. For example, research suggests pressure cooking may cause the most iodine loss, whereas a method like shallow frying may cause lower losses.
Do plant-based milks (almond, oat, soy) have as much iodine as dairy milk?
No. Plant-based milks don’t have as much iodine as dairy milk.
What are ‘goitrogens,’ and do they stop your body from using iodine?
Goitrogens are natural or man-made chemicals that can make it harder for your thyroid to absorb iodine. For goitrogens — including flavonoids, goitrins, and thiocyanates — to affect your thyroid health, you’d need to eat lots of them. Foods that have goitrogens include cruciferous veggies, such as cauliflower, kale, and broccoli, red wine, and soy products.
But most people can eat foods high in goitrogens without problems. If you have a thyroid condition, talk to your doctor about your concerns.
