Food With Iodine List is found mainly in animal protein foods and sea vegetables, and to a lesser extent in fortified foods like breads, cereals, and milk.
Iodine, a Critically Important Nutrient
An essential mineral, iodine is used by the thyroid gland to make thyroid hormones that control many functions in the body including growth and development. Because your body does not produce iodine, it needs to be supplied in the diet. When iodine intake is poor, the body cannot produce enough thyroid hormones.
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. Major international efforts are being made to help reduce the problem, mainly through the use of iodized salt and supplements.
Until the early 1900s, iodine deficiency was a common problem in the United States but was significantly improved with the addition of iodine to table salt. Hypothyroidism, thyroid gland enlargement (goiter) and weight gain are other conditions that may result from too little iodine in the diet. Many pregnant women in the U.S. continue to have insufficient iodine intakes, especially those who have low intakes of dairy, seafood and iodized salt.
Iodine and the Brain
With iodine deficiency listed as the leading cause of intellectual disability around the world, iodine is an important component for healthy brain development. The most damaging consequences are on fetal and infant development of the brain when deficiency can cause irreversible brain damage that lasts a lifetime. Brain damage, cretinism, intellectual disability and other conditions are additional risks.
It is a crucial nutrient throughout life, but especially during pregnancy, infancy and childhood when thyroid hormones regulate growth in the developing brain. Less severe iodine deficiency manifests as below average IQ in children, including impaired brain function in adults too. During childhood, iodine deficiency is often associated with goiter and also linked to reduced intellectual and motor performance, as well as an increased risk for ADHD in children.
A teaspoon of iodine is all a person requires in a lifetime, but because iodine cannot be stored for long periods, small amounts are needed regularly. The Institute of Medicine, or IOM, recommended dietary allowances for iodine are:
- 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
Best Sources of Iodine
Iodine fortification is what most countries rely on to encourage adequate dietary intake. In the more than 70 countries that iodize salt, it generally serves as the major source of iodine intake. One-fourth of a teaspoon of iodized salts has about 100 micrograms of iodine. Note that the salt used in processed foods, which is the major source of salt for most Americans, typically does not contain iodine. If salt used in a processed food contains iodine, it will be listed in the ingredients list of that food. Focus on decreasing the amount of salt consumed from processed foods and get your sodium from iodized salt.
Seaweed, saltwater fish and seafood are natural sources of dietary iodine. Dairy products also supply iodine in the diet at varying levels. During lactation, the breast concentrates iodine in milk, so breastmilk tends be a good source of iodine as long as the mother’s iodine intake is adequate.
Plants grown in iodine-rich soil are also good sources; however, this is not a reliable source of iodine since there is no way of knowing whether produce purchased in grocery stores is grown in iodine-rich soil.
Iodized salt usually adds less than about 300 micrograms iodine daily to the diet. Most multivitamin mineral supplements contain 150 micrograms of iodine. With the safe upper limit of daily iodine intake for adults set at 1,100 micrograms by the IOM, it is unlikely to hit an excess amount when including a multivitamin and including natural sources of dietary iodine.
The trend of eating less table salt, dairy and bread has some experts concerned that iodine deficiency could be on the rise again. Eating a healthy, balanced diet that includes iodine-rich foods and iodized salt is key to good health. Prenatal vitamins containing iodine can help meet nutritional needs for pregnant and lactating mothers.
If you suspect you are not getting enough iodine, consult a registered dietitian nutritionist.
7 Best Iodine Rich Foods to Boost Metabolism and Support Thyroid Health
If your metabolism is sluggish or you are overly tired or feel cold all the time, you may not be getting enough iodine in your diet. If you’re eating plant-based you’ve likely heard about the importance of getting B12, iron, and vitamin D but what about iodine? Iodine is a vital nutrient for thyroid health that has a major impact on your body’s metabolism, energy levels, and temperature regulation. Iodine deficiency can lead to thyroid disorders including hypothyroidism, where your thyroid doesn’t produce enough hormone, so it’s essential to eat foods that are rich in iodine. Fortunately, it is easy to do once you know what to look for.
Why iodine is crucial to thyroid health
“Your thyroid gland needs iodine to make hormones that are crucial for regulating your body’s different functions,” says Dr. Amelia Brown, MD, of Oregon Health and Science University Hospital in Portland, OR. Thyroid hormones are found throughout the bloodstream, so imbalances in them affect the entire body. Thyroid health is critical for many vital functions.
Dr. Elliana Rose, MD, elaborates “Iodine is required for the thyroid gland to produce two specific thyroid hormones, T3 and T4 (triiodothyronine and thyroxine). They control every cell and organ in our bodies, she explains. “They play the role of regulating metabolism.” A recent study compared the nutritional status between ‘health conscious’ vegans and non-vegans. Iodine was the only nutrient in which vegans didn’t outperform non-vegans. It’s clear plant-based eaters should focus more on getting their daily dose of iodine.
What is iodine?
Iodine is a trace mineral found in saltwater and soil in varying amounts. The most common dietary sources include iodized salt, fish, and dairy. The iodine in dairy comes from supplementation of cattle feed and the disinfectants used in milking. Not exactly whole food sources. Fish are high in iodine because they eat plenty of macroalgae which is high in iodine (and also where much of the iodine in supplements comes from).
Should you supplement iodine? Dr. Andrea Paul, MD, Co-Founder of Health Media Experts and Medical Advisor at Illuminate Labs, says, “An average healthy person has no need for supplemental iodine. Iodized salt is the most cost-effective way to increase iodine intake, but there are also food sources like seaweed that are rich in the mineral.” Iodized salt will prevent deficiency, but anyone with high blood pressure needs to be aware of the health risks associated with high sodium intakes, such as hypertension and increased risk of stroke.
Too much iodine can lead to iodine toxicity. According to Marie Salbuvik, RD, cautions, “It’s important not to exceed the Recommended Daily Allowance (RDA) of iodine as you could experience adverse health effects such as changes in how your thyroid gland works.”
Adequate daily intake for adults is 150 micrograms. Pregnant women need 220 micrograms, breastfeeding women require 290 micrograms, and children under 13 need 120 micrograms. “The reason it varies from person to person is our needs are dependent on different factors such as age, menstruation status, pregnancy status, and current supplementation,” explains Jamie Hickey, Registered Dietician and founder of Truism Fitness.
How iodine impacts thyroid health
The thyroid is a small, butterfly-shaped gland located in the middle of your neck above the collar bone that regulates your metabolism by producing hormones that control how cells use energy. Your metabolism regulates many important functions, but most people know of it because of its impact on metabolism.
Hormone imbalances can lead to hypothyroidism and hyperthyroidism. Hypothyroidism is a decrease in thyroid hormone production. Hyperthyroidism is an increase in thyroid hormone production. Certain nutrients significantly impact thyroid health, like iodine, selenium, and zinc. If you’re unsure how to include these in your diet, add the following foods that support thyroid health to your diet.
Jamie Hickey, RD, explains, “Without enough iodine, the production of important hormones can be disrupted and lead to an underactive or overactive thyroid.” Without iodine, your key thyroid becomes inflamed and metabolic processes slow down. Conversely, too much iodine can cause hormone overproduction.
How to know if you are deficient in iodine
Your body will eventually present symptoms of hypothyroidism if you’re not getting enough iodine. The most common are slowed metabolism, fatigue, cold sensitivity, weight gain, and goiters (thyroid gland enlargement). Too much iodine may cause hyperthyroidism. Symptoms include high metabolic rate, rapid heartbeat, increased blood pressure, weight loss, and mood swings. “You know you’re deficient in iodine by assessing how you feel,” Dr. Lizz Kinyua, MD,- Founder and Director of Mentor Medics, tells The Beet.
Here’s a list of seven iodine-rich foods to optimize thyroid health. It’s important to note the amount of iodine present in foods is highly variable depending on the soil’s iodine content.
7 plant-based foods rich in iodine
Dried seaweed or sea vegetables like nori, dulse, kombu, and kelp top the list as your best plant-based sources of iodine. Be sure to eat a variety of them as they contain varying amounts of iodine. Kelp is particularly rich containing up to 2,000 micrograms per tablespoon. Snack on sheets of nori, sprinkle dulse flakes on a salad, or add kombu to soup.
Cranberries may not top your favorite food list, but one ounce of the tiny red power food contains 100 micrograms of iodine. That’s 67 percent of your daily value! They also contain antioxidants and lower blood pressure. They’re a nice addition to desserts and salads, like this delicious Walnut and Cranberry Salad
One medium-sized baked potato packs 40 percent of your RDA with 60 micrograms of iodine. There’s no shortage of ways to enjoy potatoes. Make homemade french fries, bake them, mash them – just be sure to leave the skin on as that’s where the majority of iodine and other nutrients are stored.
Prunes are the highest dried fruit source of iodine. Five dried prunes provide 13 micrograms of iodine (9 percent of your RDA). They’re also an excellent source of fiber, potassium, and iron. Eat them on their own or add to trail mixes. Pro Tip: Store prunes in the freezer to make them a delicious frozen treat.
Who doesn’t love strawberries? Besides being nature’s candy, strawberries contain vitamin C, potassium and 13 micrograms of iodine per cup. Be sure to buy organic as their porous skin absorbs more pesticides than other fruits. If you’re not a fan of strawberries try buying them frozen and adding to smoothies.
One cup of cooked lima beans provides 10 percent of your daily value with 16 micrograms of iodine. Lima beans are high in fiber, magnesium, and plant protein. They’re a great addition to any salad or bowl. Try making roasted lima beans for a healthy crunchy snack.
Iodized salt is last on the list but it’s the most common source of iodine. Only a quarter teaspoon (1.5 grams) is required to reach your daily value. The drawbacks are the negative health outcomes associated with high sodium intake and the risk of getting too much iodine.
The Food and Drug Administration (FDA) and American Heart Association (AHA) recommend a maximum sodium intake of 2,300 milligrams per day (approximately 1 teaspoon of salt). The AHA advises to not exceed 1,500 milligrams a day for heart health, especially if you have high blood pressure. Reducing sodium intake by 1,000 milligrams a day can significantly lower blood pressure. The amount of sodium in salt varies depending on the type of salt, but typically a quarter teaspoon contains 550-600 milligrams of sodium. With that said, using iodized salt in moderation won’t hurt and can be a reliable way to meet your iodine needs.
Bottom line: Iodine is critical for thyroid health and is required in a healthy diet.
It’s possible to get enough iodine on a plant-based diet, and not load up on the salt. Consult your doctor or nutritionist to determine if you’re deficient in iodine and if supplementation is required.
How to treat iodine deficiency with diet and supplements
Iodine is an essential nutrient for our bodies, and it helps maintain many bodily functions. Iodine-rich foods are a staple of a healthy diet, although not everyone gets enough of this nutrient regularly. If you want to learn more about the symptoms of iodine deficiency, natural ways to ingest iodine in food, and the various types of iodine supplements that are available, keep reading.
What is iodine?
Iodine is a trace mineral that’s essential for the production of thyroid hormones triiodothyronine (T3) and thyroxine (T4). It’s a building block for sleep, metabolism, and overall growth and development. Most people get enough iodine regularly, although, in some instances, iodine supplementation may be necessary to combat a deficiency.
What is iodine deficiency?
When you have an iodine deficiency, your body isn’t getting as much iodine as it needs. “The most common cause of iodine deficiency is due to a lack of iodine in the diet,” says Kasey Nichols, NMD, who specializes in naturopathic medicine. “Iodine deficiency can lead to serious medical conditions. Fortunately, due to the inclusion of iodine in table salt in 1924, iodine deficiency in the United States is relatively uncommon.”
Although most Americans get enough iodine with a traditional Western diet, it’s important to understand the symptoms associated with an iodine imbalance and how it may impact your overall health.
Weight gain, learning difficulties, getting the chills often, and fatigue are common symptoms of an iodine deficiency. One of the more severe and prominent symptoms of an iodine deficiency is goiter, which is a bulge in the neck caused by an enlarged thyroid gland. An iodine-deficient person has an increased risk of other thyroid disorders, like hypothyroidism (a thyroid disease caused by insufficient thyroid hormone production). In the case of growing children, severe iodine deficiency can cause other health problems like intellectual disability, slow brain development, or stunted growth.
To treat an iodine deficiency, a person can increase their intake of certain iodine-rich foods, or take iodine supplements.
How do I know if I need iodine?
The first step in diagnosing an iodine deficiency is to contact your healthcare provider. He or she will be able to test your iodine levels in a variety of ways to determine if you lack dietary iodine. There are a few different tests that can help with this process.
The two most common iodine tests are a urine test and a blood test, which are both quick and easy ways to check levels of iodine. However, the urinalysis may not be as accurate as a blood test. Another option is a more in-depth urine loading test, which shows iodine concentration in your urine over 24 hours. This is a highly accurate test, although it can be inconvenient to obtain all urine samples for an entire day. Lastly, the iodine patch test also takes around 24 hours to complete, but it’s not as precise. With this test, your physician will paint a patch of skin with iodine and observe how quickly the body absorbs it.
Depending on the results of these tests and the patient’s symptoms, a doctor may need to perform additional tests like a TSH test to determine thyroid hormone levels and how they may have been affected by low levels of iodine.
How much iodine do I need?
Since iodine is a necessary component for proper thyroid function and developmental growth, the amount of iodine a person needs depends on their life stage.
Below is a list of the recommended daily intake for iodine consumption, according to the National Institutes of Health:
|Daily iodine intake recommendations|
|Life stage||Recommended daily intake|
|Birth to 6 months||110 mcg|
|Infants 7–12 months||130 mcg|
|Children 1–8 years||90 mcg|
|Children 9–13 years||120 mcg|
|Teens 14–18 years||150 mcg|
|Pregnant women||220 mcg|
|Breastfeeding women||290 mcg|
Note: Pregnant and breastfeeding women need the most iodine, as their iodine levels pass on to their child during development. Because of this, lactating women have the highest recommended amount of iodine consumption to ensure that their breast milk contains enough iodine for their baby.
How much iodine is too much?
Maximum iodine requirements also fluctuate by life stage. For instance, a young child shouldn’t exceed 300 mcg of iodine in a day, while a full-grown adult has an upper limit of 1,100 mcg. Too much iodine can produce similar symptoms as iodine deficiency, like goiter or hyperthyroidism.
What are good sources of iodine in food?
Iodized table salt resolved a lot of iodine deficiency disorders in the 20s, however, data suggests an iodine deficiency problem could be remerging in the U.S. as more consumers opt for non-iodized kosher salt and sea salt.
Fortunately, there are many iodine-rich foods available besides salt. You can look to dairy products (particularly milk and eggs) and seafood (fish, shrimp, and seaweed) to incorporate more iodine in your diet. Fruits and vegetables are also good food sources of iodine, especially lima beans, bananas, or corn.
Some of the most common iodine-rich foods and their percent daily values (%DV) are listed below. These numbers come from the National Institutes of Health recommendations for iodine food consumption.
|Food||Iodine micrograms per serving||Percent daily value (%DV)|
|Seaweed (Nori, Kombu, Wakambe, Arame)||Ranges between 16-2,984 mcg per 1 gram of seaweed||11%-1,989%|
|Cod||99 mcg in 3 oz of baked cod||66%|
|Milk||56 mcg per 1 cup of reduced-fat milk||37%|
|Bread||45 mcg per 2 slices of white, enriched bread||30%|
|Shrimp||35 mcg per 3 oz of shrimp||23%|
|Eggs||24 mcg per egg||16%|
|Tuna||17 mcg per 3 oz of tuna (canned in oil)||11%|
|Lima beans||8 mcg per ½ cup of boiled lima beans||5%|
|Corn||14 mcg per ½ cup of creamed corn||9%|
|Banana||3 mcg per 1 banana||2%|
Can you take iodine supplements?
Iodine supplements are available over-the-counter as capsules or tablets. Some of them are derived from iodine-rich kelp (a type of seaweed). These products don’t require a prescription, but it is necessary to differentiate them from other iodine formulations.
It’s is an essential nutrient for our bodies, but iodine can also be used as a first-aid antiseptic to treat minor cuts or wounds and prevent infection. Iodine tinctures and other liquid-based forms of iodine are designed for external use only and should not be ingested.
Lugol’s solution, which contains potassium iodide, is not intended to be used as a supplement. It can be ingested under the supervision of a doctor in the treatment of thyrotoxicosis (thyroid storm) or radiation emergencies. Do not ingest an iodine-containing liquid without the guidance and supervision of a medical professional.
If you intend to take an iodine supplement, it’s best to seek medical advice from your healthcare provider or dietitian about the best products to use, and what dosage is right for you. Typically, these kinds of supplements contain an iodine content of 150 mcg, which is the standard amount of iodine that an adult should get daily. However, everyone is different when it comes to nutritional needs, and eating more iodine-rich foods can be a better treatment option for some individuals.