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    Iodine is an essential component of the thyroid hormonal agents, which are required for normal development and development, especially of the brain and central nervous system. A lack of iodine in the diet is the single most typical cause of preventable mental retardation on the planet. [1]


    Iodine was first discovered by Barnard Courtois, a French chemist in 1811 while extracting potassium and sodium from seaweed ash. When he unintentionally added sulfuric acid, a violet colored cloud developed from the mass. The resulting gas was condensed into dark crystals-the first occurrence of observed solid iodine. [2]

    Event and distribution

    Iodine is never ever discovered in nature uncombined, and it is not concentrated adequately to form independent minerals. It exists in seawater, but sparingly, as the iodide ion, I −, to the extent of around 50 mg per metric heap (0.0016 ounce per ton) of seawater. It is also formed in seaweeds, oysters, and cod livers. Salt iodate (NaIO3) is contained in unrefined Chile saltpetre (salt nitrate, NaNO3). The body includes iodine in the compound thyroxine, which is produced in the thyroid gland.

    The only naturally taking place isotope of iodine is steady iodine-127. An exceptionally useful radioactive isotope is iodine-131, which has a half-life of eight days. It is employed in medicine to keep track of thyroid gland working, to deal with goitre and thyroid cancer, and to find tumours of the brain and of the liver. It is likewise used in examinations to trace the course of substances in metabolic process. Numerous iodine compounds are utilized as contrast mediums in diagnostic radiology. In liquid service even minute amounts of iodine in the presence of starch produce a blue-black colour. [3]

    Facts About Iodine

    Iodine is an essential element required for life. It is best understood for the important role it plays in thyroid hormone production in people as well as in all vertebrates. Iodine deficiency can result in serious health issue, including goiter (enlarged thyroid gland), intellectual special needs and cretinism.

    As a pure element, iodine is a shiny purple-black nonmetal that is solid under standard conditions. It sublimes (modifications from a strong to a gaseous state while bypassing a liquid type) easily and gives off a purple vapor. Although it is technically a non-metal, it displays some metallic qualities.

    Iodine is classified as a halogen– a subset of extremely chemically reactive aspects (Group 17 on the periodic table) that exist in the environment as compounds rather than as pure aspects. The other halogens consist of fluorine (F), chlorine (Cl), bromine (Br) and astatine (At). The term halogen indicates “salt-producing.” When these elements react with metals, they produce a wide array of salts, such as calcium fluoride, sodium chloride (common table salt), silver bromide and potassium iodide.

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    Iodine gas

    Iodine can sublimate into a violet-pink gas.

    Iodine is an essential element required for life. It is best understood for the essential function it plays in thyroid hormonal agent production in humans as well as in all vertebrates. Iodine deficiency can lead to serious health problems, consisting of goiter (enlarged thyroid gland), intellectual disability and cretinism.

    As a pure aspect, iodine is a lustrous purple-black nonmetal that is strong under basic conditions. It sublimes (modifications from a solid to a gaseous state while bypassing a liquid form) easily and gives off a purple vapor. Although it is technically a non-metal, it shows some metallic qualities.

    Iodine is classified as a halogen– a subset of very chemically reactive components (Group 17 on the periodic table) that exist in the environment as compounds rather than as pure aspects. The other halogens consist of fluorine (F), chlorine (Cl), bromine (Br) and astatine (At). The term halogen implies “salt-producing.” When these elements respond with metals, they produce a wide variety of salts, such as calcium fluoride, sodium chloride (common table salt), silver bromide and potassium iodide.

    Iodine is the least reactive of the halogens along with the most electropositive, suggesting it tends to lose electrons and form positive ions throughout chain reaction. It is also the heaviest and the least plentiful of the stable halogens. There are 30 recognized isotopes of iodine, but only one is naturally taking place (I-127).

    Iodine has a number of industrial applications and can be found in a variety of pharmaceuticals, disinfectants, inks and dyes, drivers, photography chemicals and animal feed supplements. It plays an especially popular role in medication. For instance, iodine substances are commonly utilized as decontaminating and wound-cleansing options and as internal contrasting representatives in imaging methods such as computed tomography (CT) scans, radiography and fluoroscopy. The radioactive isotope iodine-131 is likewise utilized to deal with cancer in the thyroid gland.

    Trace element

    About 99.6 percent of the Earth’s mass is a mix of 32 chemical elements, according to the World Iodine Association (WIA). The remaining 0.4 percent is divided amongst 64 aspects– all of these in trace amounts. Iodine is the 61st aspect in terms of abundance, making it not only one of the least plentiful nonmetallic aspects in the world but also one of the rarest components needed for life.

    Although iodine is not especially abundant, it can be discovered in trace amounts almost all over: water, soil, rocks, plants, animals and people. Seawater is the largest reserve of iodine, holding about 34.5 million tons. However the concentrations are so low– balancing in between 50 to 60 parts per billion (ppb)– that direct extraction is not practical. Rivers include less iodine, at around 5 ppb, according to Lenntech Water Treatment Solutions of Denmark.

    Most of the world’s commercial iodine is gotten from salt water (water strongly filled in salt) associated with gas wells in Japan and from caliche ore mined in the Atacama Desert of northern Chile. In the United States, iodine is stemmed from deep well brines in northern Oklahoma.

    Facts in summary

    • Atomic number (number of protons in the nucleus): 53
    • Atomic sign (on the table of elements of the elements): I
    • Atomic weight (average mass of the atom): 126.90447
    • Density: 4.93 grams per cubic centimeter
    • Stage at room temperature: Solid
    • Melting point: 236.7 degrees Fahrenheit (113.7 degrees Celsius)
    • Boiling point: 363.9 F (184.4 C)
    • Number of isotopes (atoms of the exact same aspect with a various variety of neutrons): 37 known isotopes; one stable (I-127)

    Who knew?

    The very first iodized salt was offered in Michigan in 1924. Before this, the majority of people living along the coasts still got a lot of iodine simply by being near the ocean and the coastal soil. Individuals living further inland, nevertheless, were often iodine-deficient, leading to a higher occurrence of goiter. As soon as the connection in between iodine shortage and goiter was developed, public health authorities began trying to find ways to reduce the problem– ultimately resulting in iodized salt.

    Iodine is a good test for starch as it turns a deep blue color when it is available in contact with it.

    Photography was the first industrial use for iodine. In 1839, Louis Daguerre created an approach for producing images, called daguerreotypes, on thin sheets of metal.

    Even animals can develop goiters due to iodine deficiency. It is not uncommon to see goiters in canines, cattle, goats, birds and fish.

    Iodine is a component of nuclear fallout, the recurring radioactive material that falls from the sky after a nuclear blast. People in a radioactive location are in threat of inhaling or consuming iodine, which is highly toxic in big dosages. [4]

    Uses of iodine

    Iodine is thought about an essential mineral for our bodies. It’s particularly crucial during pregnancy, and exposure in the womb might even help prevent particular health conditions later on in life.

    The following is a list of some of the most essential usages and how they benefit the body.

    1. Promoting thyroid health

    Iodine plays a vital function in thyroid health. Your thyroid gland, which lies at the base of the front of your neck, assists manage hormonal agent production. These hormones control your metabolic process, heart health, and more.

    To make thyroid hormonal agents, your thyroid uses up iodine in percentages. Without iodine, thyroid hormone production can reduce. A “low” or underactive thyroid gland can result in a condition called hypothyroidism.

    Offered the wide availability of iodine in western diet plans, thyroid health isn’t usually impacted by low iodine levels in the United States.

    You can get enough iodine from your diet by eating dairy items, strengthened foods, and seawater fish. Iodine is likewise readily available in plant foods that grow in naturally iodine-rich soil. You also can get the mineral by seasoning your food with iodized salt.

    While iodine promotes general thyroid health, too much iodine can have an unfavorable effect on the thyroid gland. That’s why you should not take iodine supplements without your physician’s suggestion.

    2. Lowering risk for some goiters

    A goiter is an enlarged thyroid gland. Your thyroid may become enlarged as a result from either hypothyroidism or hyperthyroidism. Hyperthyroidism is an overactive thyroid gland.

    Non-cancerous thyroid nodules (cysts) can likewise trigger thyroid gland enhancement.

    Sometimes a goiter establishes as a direct action to iodine deficiency. This is the most typical cause of goiter worldwide, though it’s not as common a cause in the United States and other nations with access to iodine-rich foods.

    Iodine-induced goiters may be reversed by including iodine-rich foods or supplements in the diet plan.

    3. Managing overactive thyroid gland

    Your medical professional might recommend an unique type of iodine called radioactive iodine to treat an overactive thyroid gland. Likewise called radioiodine, this medication is taken by mouth. It’s used to destroy additional thyroid cells to help in reducing extreme amounts of thyroid hormone.

    The risk with radioactive iodine is that it can damage a lot of thyroid cells. This can reduce the amount of hormone production, causing hypothyroidism. For this reason, radioactive iodine is normally only suggested after anti-thyroid drugs have actually stopped working.

    Radioactive iodine is not the exact same thing as iodine supplements. You need to never take iodine supplements for hyperthyroidism.

    4. Treating thyroid cancer

    Radioiodine may also be a possible treatment alternative for thyroid cancer. It works in much the same way as hyperthyroid treatment.

    When you take radioactive iodine orally, the medication destroys thyroid cells, consisting of cancerous ones. It might be utilized as a treatment following thyroid surgical treatment to make certain all cancerous cells have been removed from the body.

    According to the American Cancer Society, radioactive iodine treatments significantly improve the opportunities of survival for people with thyroid cancer.

    5. Neurodevelopment during pregnancy

    You require more iodine in pregnancy. That’s due to the fact that iodine intake during pregnancy is linked to brain advancement in fetuses. One review discovered that babies whose birth mothers had an iodine deficiency during pregnancy were most likely to grow up with lower IQ’s and other intellectual hold-ups.

    The advised everyday intake of iodine during pregnancy is 220 mcg. By comparison, the suggested quantity in non-pregnant grownups is 150 mcg a day.

    If you’re pregnant, ask your doctor about iodine supplements, specifically if your prenatal vitamin does not have iodine (many do not). Iodine supplements may likewise be essential if you’re deficient in the mineral.

    You’ll likewise need to continue monitoring your iodine intake if you’re breastfeeding. The advised day-to-day quantity of iodine while nursing is 290 mcg. That’s due to the fact that the iodine you take up from diet plan and supplements is transferred by means of breast milk to your nursing baby. This is an important brain developmental period, so babies require 110 mcg each day up until they’ve reached 6 months of age.

    6. Improving cognitive function

    The very same neurological advantages of iodine during pregnancy might reach healthy brain function during childhood. This likewise includes a reduced risk of intellectual disability.

    It is likely your child gets all the iodine they need through their diet plan, but if you have any questions about their iodine consumption, talk to their pediatrician.

    7. Improving birth weight

    As with brain development, iodine during pregnancy is related to a healthy birth weight. One study of pregnant women with goiters discovered that 400 mg of iodine taken daily for 6 to eight weeks was valuable in correcting goiters associated with iodine shortage. In turn, there was an overall improvement in birth weight in newborns.

    While iodine consumption can affect an infant’s birth weight and general advancement, it is very important to note that the above study focused on females in developing locations who were already lacking in iron.

    Unless your medical professional has identified you are iodine deficient, taking supplements aren’t likely to affect your child’s weight at birth. In fact, taking iodine unnecessarily can trigger health issues.

    8. May aid treat fibrocystic breast disease

    It’s possible that iodine supplements or medications can help deal with fibrocystic breast illness. This non-cancerous condition is most common in women of reproductive age, and it can cause uncomfortable breast swellings.

    Although there is some guarantee that iodine might aid with fibrocystic breast cysts, you should not try self-treatment. Just take iodine for this condition if your doctor particularly recommends it. Otherwise, you could be at risk of adverse effects from iodine toxicity.

    9. Disinfecting water

    Iodine is just one method of water disinfection. This might be especially helpful if you do not have access to safe and clean water due to taking a trip or results from a natural disaster.

    Two percent liquid iodine cast may be contributed to water in five-drop increments per one quart of clear water. If the water is cloudy, include ten drops per quart.

    Iodine tablets may likewise be utilized, but the directions can vary by manufacturer.

    Despite the role iodine can play in disinfecting drinking water, there’s also some concerns that it can increase overall iodine intake in humans and result in adverse health impacts. Total iodine consumption shouldn’t go beyond 2 mg per day.

    10. Protection from nuclear fallout

    When it comes to nuclear emergencies, the Centers for Illness Control and Prevention suggests the use of potassium iodide (KI) to secure the thyroid gland from radiation injuries. These are available in tablet and liquid solutions.

    While not totally foolproof, the sooner KI is taken, the better the thyroid is believed to be safeguarded in case of this type of emergency.

    There are major threats related to KI, including gastrointestinal upset, swelling, and allergic reaction. You’re also at increased threat for thyroid disease. Your threat for problems is higher if you already have thyroid illness.

    11. Dealing with infections

    Iodine can be used topically in a liquid kind to assist treat and prevent infections. It works by eliminating germs around mild cuts and scrapes.

    Topical iodine needs to not be utilized on newborn babies. It ought to likewise not be used for deep cuts, animal bites, or burns.

    Follow instructions on the product packaging for dose info, and do not utilize for more than 10 days unless directed by your medical professional. [5]

    Tools to improve iodine levels

    1. Be mindful of salt

    Switching to sea salt is one way to guarantee you aren’t overdoing it on iodine. While sea salt does consist of a small amount of naturally-occurring iodine, it’s not enough to make a substantial difference in your total iodine levels for that reason this shouldn’t be something to rely on if you are wanting to include more iodine into your diet plan.

    2. Focus on iodine-rich foods

    Sea veggies like seaweed, dulse, and kelp are a typically neglected food medication that is packed with iodine. Kelp’s iodine levels are sky-high, with some varieties having up to 2,984 micrograms it has the highest iodine content of any sea veggie. Kombu, a specific variety of kelp, has the greatest iodine content.

    Some other higher sources of iodine include:.

    • Cod (3 oz.) – 158 mcg
    • Oysters (3 oz.) – 93 mcg
    • Egg (1 cooked) – 26 mcg

    3. Supplements

    The advised consumption of iodine differs for each individual but in general males and females ought to be getting 150 mcg of iodine each day and pregnant females 220 mcg each day. If you identify that supplementation is essential, deal with your doctor to identify the best dose for you. [6]

    Signs of Deficiency and Toxicity


    Iodine controls metabolism, the conversion of energy gotten from food into energy to assist cells function and grow. A deficiency of iodine can for that reason avoid typical development and development. This is particularly unsafe in pregnant females and infants, in which miscarriage, stillbirth, stunted development, and cognitive disabilities (troubles with reading, writing, talking, issue fixing, social skills) can happen. In grownups, an iodine deficiency of less than 10-20 mcg a day can cause insufficient thyroid hormonal agent production, called hypothyroidism, which interferes with regular metabolic functions like managing heart rate, body temperature, and body weight. A lump or swelling in the neck, called goiter, often accompanies hypothyroidism. Other indications of hypothyroidism include:.

    • Tiredness, sleepiness
    • Weak point
    • Sensitivity to cold
    • Constipation
    • Dry skin and hair
    • Weight gain

    Individuals at risk for iodine deficiency consist of those who do not use iodized salt or supplements including iodine, pregnant ladies, vegans who do not eat any animal foods, and those living in locations with low levels of iodine in the soil (e.g., mountainous regions).


    High iodine intakes are normally well-tolerated in a lot of healthy people and do not trigger problems. This has actually been observed in countries such as Japan and Korea that consume iodine-rich seaweed routinely. However some people with autoimmune thyroid disease or who have a history of persistent iodine shortage can be conscious receiving additional iodine, causing conditions of iodine shortage like hypothyroidism and goiter. Excess iodine can likewise lead to excessive thyroid hormonal agent production, causing hyperthyroidism; signs of this condition are an increased metabolic process that promotes weight-loss, fast or irregular heartbeat, hand tremors, irritability, fatigue, and sweatiness. Sometimes even simply a small increase in dietary iodine above the RDA can trigger iodine-induced hyperthyroidism in sensitive people.

    Some epidemiologic studies have shown that high seaweed consumptions are connected with an increased danger of particular types of thyroid cancer, particularly in postmenopausal females, however the exact mechanism is unclear.

    Excess iodine consumption might originate from use of high-dose supplements or overeating certain seaweeds and salts that contain iodine. Extreme iodine poisoning is rare, but signs include fever; stomach discomfort; nausea; vomiting; a burning sensation of the mouth, throat, and stomach; and even coma. [2] Kids, infants, the elderly, and those with existing thyroid disease are especially vulnerable to iodine toxicity and iodine-induced hypothyroidism and hyperthyroidism.

    Did You Know?

    In the U.S., people obtain most of their dietary iodine from iodized salt and milk.

    Iodine supplements can connect with certain blood pressure medications and diuretics, including lisinopril, spironolactone, and amiloride, causing an unsafe accumulation of potassium in the blood called hyperkalemia.

    Iodine is an active ingredient in contrast representatives that a person may take previously having an X-ray or computed tomography (CT scan). It helps to absorb the rays so that clearer pictures of the body’s organs can be seen. [7]

    Suggested intake

    The suggested intake of iodine from the age of 14 years is 150 microgramsTrusted Source (mcg) for both males and females. During pregnancy, it is 220 mcg, rising to 290 mcg while breastfeeding.

    Food is the very best source of iodine.

    The quantity of iodine in a food depends upon how much iodine there is at the source of production.

    The quantity of iodine in the soil where crops are grown, or where an animal is raised for meat will impact the quantity of iodine in the food. Produce from the sea is an excellent source of iodine.

    Levels of iodine in food differ according to where it originates from. In vegetables and fruit, it can range from 10 mcg per kilogram of dry weight to 1 gram.

    Because of this variation, the iodine content in foods is typically approximate. [8]

    Extreme quantities of iodine can be harmful

    Having excessive iodine, for example via supplements, can trigger a few of the very same problems as iodine shortage (such as goitre). The level of iodine thought about to be excessive, and the symptoms experienced, can differ from person-to-person, depending on underlying health conditions.

    If you believe you’re not getting adequate iodine in your diet talk to your doctor or an accredited practicing dietitian before beginning on any supplements. [9]


    Moderate Interaction.

    Be cautious with this mix.

    Amiodarone (Cordarone) communicates with IODINE

    Amiodarone includes iodine. Taking iodine supplements along with amiodarone may increase the levels of iodine in the blood. Too much iodine in the blood can cause side effects that affect the thyroid.

    Lithium engages with IODINE

    Large amounts of iodine can decrease thyroid function. Lithium can likewise reduce thyroid function. Taking iodine in addition to Lithium may decrease thyroid function too much. Do not take large quantities of iodine if you are taking Lithium.

    Medications for an overactive thyroid (Antithyroid drugs) communicates with IODINE

    Iodine can increase or reduce thyroid function. Taking iodine in addition to medications for an overactive thyroid might alter the results of these medications. Do not take iodine supplements if you are taking medications for an overactive thyroid, unless recommended by a doctor. [10]


    Iodine is an essential nutrient. Individuals with access to iodized salt, seafood, and certain vegetables have the ability to get enough iodine from their diet plan.

    Sometimes, you may require iodine supplements to help in reducing your danger for iodine shortage, or as a treatment for certain medical conditions, such as underactive thyroid or goiter.

    Talk with your physician about your specific iodine needs. [11]



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