Iodine is an integral element of the thyroid hormones, which are required for typical development and advancement, especially of the brain and main nervous system. An absence of iodine in the diet is the single most typical reason for preventable mental retardation on the planet. [1]


Iodine was first discovered by Barnard Courtois, a French chemist in 1811 while drawing out potassium and salt from seaweed ash. When he unintentionally included 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]

Occurrence and distribution

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

The only naturally occurring isotope of iodine is steady iodine-127. An exceptionally beneficial radioactive isotope is iodine-131, which has a half-life of 8 days. It is used in medication to monitor thyroid gland operating, to deal with goitre and thyroid cancer, and to find tumours of the brain and of the liver. It is likewise utilized in investigations to trace the course of substances in metabolism. Numerous iodine substances are utilized as contrast mediums in diagnostic radiology. In liquid service even minute amounts of iodine in the existence of starch produce a blue-black colour. [3]

Truths About Iodine

Iodine is an essential element required for life. It is best known for the crucial function it plays in thyroid hormone production in humans as well as in all vertebrates. Iodine shortage can cause major illness, including goiter (enlarged thyroid gland), intellectual impairment and cretinism.

As a pure element, iodine is a shiny purple-black nonmetal that is solid under standard conditions. It sublimes (changes from a solid to a gaseous state while bypassing a liquid kind) easily and produces a purple vapor. Although it is technically a non-metal, it exhibits some metal qualities.

Iodine is classified as a halogen– a subset of really chemically reactive elements (Group 17 on the table of elements) that exist in the environment as substances instead of as pure aspects. The other halogens include fluorine (F), chlorine (Cl), bromine (Br) and astatine (At). The term halogen suggests “salt-producing.” When these aspects react with metals, they produce a wide variety of salts, such as calcium fluoride, sodium chloride (typical 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 needed for life. It is best known for the crucial function it plays in thyroid hormonal agent production in human beings as well as in all vertebrates. Iodine shortage can lead to major illness, including goiter (bigger thyroid gland), intellectual disability and cretinism.

As a pure component, iodine is a shiny purple-black nonmetal that is solid under basic conditions. It sublimes (changes from a strong to a gaseous state while bypassing a liquid type) quickly and emits a purple vapor. Although it is technically a non-metal, it displays some metallic qualities.

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

Iodine is the least reactive of the halogens along with the most electropositive, implying it tends to lose electrons and form positive ions during chemical reactions. It is also the heaviest and the least abundant of the stable halogens. There are 30 known isotopes of iodine, but only one is naturally occurring (I-127).

Iodine has several industrial applications and can be found in a range of pharmaceuticals, disinfectants, inks and dyes, catalysts, photography chemicals and animal feed supplements. It plays a particularly popular function in medication. For instance, iodine substances are commonly used as disinfecting and wound-cleansing services and as internal contrasting agents in imaging strategies such as computed tomography (CT) scans, radiography and fluoroscopy. The radioactive isotope iodine-131 is also used to treat cancer in the thyroid gland.


About 99.6 percent of the Earth’s mass is a mixture of 32 chemical components, according to the World Iodine Association (WIA). The remaining 0.4 percent is divided among 64 aspects– all of these in trace amounts. Iodine is the 61st element in terms of abundance, making it not only one of the least abundant nonmetallic elements on Earth however likewise among the rarest elements needed for life.

Although iodine is not especially plentiful, it can be discovered in trace amounts almost everywhere: water, soil, rocks, plants, animals and humans. Seawater is the biggest reserve of iodine, holding about 34.5 million loads. But the concentrations are so low– averaging in between 50 to 60 parts per billion (ppb)– that direct extraction is not possible. Rivers contain less iodine, at around 5 ppb, according to Lenntech Water Treatment Solutions of Denmark.

The majority of the world’s commercial iodine is gotten from brines (water highly filled in salt) related to 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.

Truths in summary

  • Atomic number (number of protons in the nucleus): 53
  • Atomic sign (on the periodic table of the aspects): I
  • Atomic weight (typical mass of the atom): 126.90447
  • Density: 4.93 grams per cubic centimeter
  • Phase at space temperature level: Strong
  • Melting point: 236.7 degrees Fahrenheit (113.7 degrees Celsius)
  • Boiling point: 363.9 F (184.4 C)
  • Variety of isotopes (atoms of the same component with a different variety of neutrons): 37 recognized isotopes; one stable (I-127)

Who understood?

The first iodized salt was sold in Michigan in 1924. Before this, most people living along the coasts still got lots of iodine just by being near the ocean and the seaside soil. People living more inland, nevertheless, were frequently iodine-deficient, resulting in a higher incidence of goiter. When the connection between iodine deficiency and goiter was established, public health officials started trying to find methods to ease the issue– ultimately causing iodized salt.

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

Photography was the first commercial usage for iodine. In 1839, Louis Daguerre created a technique for producing images, called daguerreotypes, on thin sheets of metal.

Even animals can establish goiters due to iodine shortage. It is not rare to see goiters in pets, livestock, goats, birds and fish.

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

Uses of iodine

Iodine is considered a necessary mineral for our bodies. It’s particularly essential during pregnancy, and direct exposure in the womb may even assist avoid certain health conditions later in life.

The following is a list of a few of the most crucial uses and how they benefit the body.

1. Promoting thyroid health

Iodine plays a vital role in thyroid health. Your thyroid gland, which lies at the base of the front of your neck, helps control hormone production. These hormonal agents control your metabolism, heart health, and more.

To make thyroid hormonal agents, your thyroid takes up iodine in small amounts. Without iodine, thyroid hormonal agent production can decrease. A “low” or underactive thyroid gland can lead to a condition called hypothyroidism.

Given the wide accessibility of iodine in western diet plans, thyroid health isn’t typically affected by low iodine levels in the United States.

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

While iodine promotes total thyroid health, excessive iodine can have a negative effect on the thyroid gland. That’s why you shouldn’t take iodine supplements without your physician’s suggestion.

2. Reducing risk for some goiters

A goiter is a bigger 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 enlargement.

In some cases a goiter develops as a direct action to iodine shortage. This is the most common cause of goiter worldwide, though it’s not as typical a cause in the United States and other countries with access to iodine-rich foods.

Iodine-induced goiters might be reversed by adding iodine-rich foods or supplements in the diet.

3. Managing overactive thyroid gland

Your doctor might advise 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 ruin extra thyroid cells to help in reducing extreme amounts of thyroid hormone.

The risk with radioactive iodine is that it can ruin too many thyroid cells. This can reduce the quantity of hormone production, resulting in hypothyroidism. For this reason, radioactive iodine is usually just recommended after anti-thyroid drugs have actually failed.

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

4. Dealing with 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 ruins thyroid cells, consisting of cancerous ones. It might be utilized as a treatment following thyroid surgery to ensure all cancerous cells have actually been gotten rid of from the body.

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

5. Neurodevelopment during pregnancy

You need more iodine in pregnancy. That’s due to the fact that iodine intake during pregnancy is linked to brain development in fetuses. One review discovered that infants whose birth mothers had an iodine shortage during pregnancy were most likely to mature with lower IQ’s and other intellectual delays.

The suggested daily consumption of iodine during pregnancy is 220 mcg. By comparison, the recommended quantity in non-pregnant adults is 150 mcg a day.

If you’re pregnant, ask your medical professional about iodine supplements, especially if your prenatal vitamin does not have iodine (many do not). Iodine supplements might also be needed if you lack the mineral.

You’ll also require to continue monitoring your iodine consumption if you’re breastfeeding. The advised everyday amount of iodine while nursing is 290 mcg. That’s due to the fact that the iodine you take up from diet plan and supplementation is transferred by means of breast milk to your nursing infant. This is a vital brain developmental period, so infants need 110 mcg each day up until they’ve reached 6 months of age.

6. Improving cognitive function

The same neurological benefits of iodine during pregnancy might reach healthy brain function throughout youth. This likewise consists of a decreased threat of intellectual special needs.

It is most likely your kid gets all the iodine they need through their diet, however if you have any questions about their iodine consumption, speak with their pediatrician.

7. Improving birth weight

As with brain advancement, iodine during pregnancy is related to a healthy birth weight. One research study of pregnant women with goiters discovered that 400 mg of iodine taken daily for six to 8 weeks was handy in fixing goiters connected to iodine shortage. In turn, there was a general improvement in birth weight in babies.

While iodine consumption can affect a baby’s birth weight and total development, it is very important to note that the above study focused on females in developing areas who were currently lacking in iron.

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

8. May assistance treat fibrocystic breast illness

It’s possible that iodine supplements or medications can help treat fibrocystic breast disease. This non-cancerous condition is most common in women of reproductive age, and it can trigger agonizing breast lumps.

Although there is some assure that iodine might help with fibrocystic breast cysts, you should not attempt self-treatment. Only take iodine for this condition if your medical professional particularly suggests it. Otherwise, you could be at risk of adverse effects from iodine toxicity.

9. Sanitizing water

Iodine is simply one approach of water disinfection. This might be specifically useful if you don’t have access to safe and clean water due to traveling or effects from a natural catastrophe.

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

Iodine tablets might also be utilized, but the directions can differ by maker.

In spite of the function iodine can play in sanitizing drinking water, there’s likewise some issues that it can increase overall iodine intake in people and cause unfavorable health results. Total iodine intake should not exceed 2 mg each day.

10. Protection from nuclear fallout

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

While not entirely foolproof, the sooner KI is taken, the much better the thyroid is thought to be safeguarded in case of this sort of emergency.

There are major dangers associated with KI, including gastrointestinal upset, swelling, and allergic reaction. You’re likewise at increased threat for thyroid illness. Your risk for issues is greater if you currently have thyroid illness.

11. Treating infections

Iodine can be utilized topically in a liquid form to assist deal with and avoid infections. It works by eliminating germs in and around mild cuts and scrapes.

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

Follow directions on the product packaging for dose information, and do not use for more than 10 days unless directed by your physician. [5]

Tools to enhance iodine levels

1. Bear in mind salt

Switching to sea salt is one method to guarantee you aren’t overdoing it on iodine. While sea salt does include a percentage of naturally-occurring iodine, it’s not enough to make a substantial difference in your overall iodine levels for that reason this should not be something to rely on if you are aiming to integrate more iodine into your diet plan.

2. Concentrate on iodine-rich foods

Sea vegetables like seaweed, dulse, and kelp are a typically neglected food medicine 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 vegetable. Kombu, a particular variety of kelp, has the highest iodine material.

Some other greater sources of iodine include:.

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

3. Supplements

The suggested intake of iodine differs for each person but in general males and females need to be getting 150 mcg of iodine per day and pregnant ladies 220 mcg daily. If you figure out that supplements is necessary, work with your medical professional to determine the right dosage for you. [6]

Signs of Deficiency and Toxicity


Iodine regulates metabolism, the conversion of energy acquired from food into energy to assist cells function and grow. A deficiency of iodine can therefore avoid regular development and development. This is especially unsafe in pregnant females and infants, in which miscarriage, stillbirth, stunted development, and cognitive disabilities (troubles with reading, composing, talking, problem fixing, social skills) can occur. In adults, an iodine deficiency of less than 10-20 mcg a day can cause inadequate thyroid hormone production, called hypothyroidism, which disrupts regular metabolic functions like controling heart rate, body temperature, and body weight. A swelling or swelling in the neck, called goiter, often accompanies hypothyroidism. Other signs of hypothyroidism consist of:.

  • Fatigue, lethargy
  • Weak point
  • Level of sensitivity to cold
  • Constipation
  • Dry skin and hair
  • Weight gain

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


High iodine intakes are normally well-tolerated in the majority of healthy people and do not trigger issues. This has actually been observed in countries such as Japan and Korea that consume iodine-rich seaweed frequently. But some people with autoimmune thyroid illness or who have a history of chronic iodine shortage can be conscious getting additional iodine, causing conditions of iodine shortage like hypothyroidism and goiter. Excess iodine can also result in too much thyroid hormonal agent production, causing hyperthyroidism; indications of this condition are an increased metabolism that promotes weight-loss, fast or irregular heartbeat, hand tremblings, irritation, fatigue, and sweatiness. Sometimes even simply a slight increase in dietary iodine above the RDA can cause iodine-induced hyperthyroidism in sensitive individuals.

Some epidemiologic research studies have shown that high seaweed consumptions are associated with an increased risk of certain types of thyroid cancer, especially in postmenopausal women, but the precise system is uncertain.

Excess iodine intake might originate from use of high-dose supplements or overeating particular seaweeds and salts that contain iodine. Extreme iodine poisoning is uncommon, but signs consist of fever; stomach discomfort; nausea; throwing up; a burning experience of the mouth, throat, and stomach; and even coma. [2] Children, infants, the elderly, and those with existing thyroid disease are particularly vulnerable to iodine toxicity and iodine-induced hypothyroidism and hyperthyroidism.

Did You Know?

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

Iodine supplements can interact with particular blood pressure medications and diuretics, including lisinopril, spironolactone, and amiloride, causing a dangerous accumulation of potassium in the blood called hyperkalemia.

Iodine is an active ingredient on the other hand agents that an individual may take in the past having an X-ray or computed tomography (CT scan). It assists to soak up the rays so that clearer images of the body’s organs can be seen. [7]

Recommended consumption

The advised 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 best source of iodine.

The amount of iodine in a food depends on just how much iodine there is at the source of production.

The amount of iodine in the soil where crops are grown, or where an animal is raised for meat will affect the quantity of iodine in the food. Produce from the sea is a good 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 frequently approximate. [8]

Excessive quantities of iodine can be harmful

Having too much iodine, for example through supplements, can cause a few of the same problems as iodine deficiency (such as goitre). The level of iodine considered to be excessive, and the signs experienced, can differ from person-to-person, depending on underlying health conditions.

If you think you’re not getting sufficient iodine in your diet plan talk to your doctor or a certified practicing dietitian before beginning on any supplements. [9]


Moderate Interaction.

Be cautious with this mix.

Amiodarone (Cordarone) connects with IODINE

Amiodarone includes iodine. Taking iodine supplements together with amiodarone might increase the levels of iodine in the blood. Too much iodine in the blood can trigger side effects that affect the thyroid.

Lithium engages with IODINE

Big amounts of iodine can decrease thyroid function. Lithium can also decrease thyroid function. Taking iodine in addition to lithium might reduce thyroid function too much. Do not take large quantities of iodine if you are taking lithium.

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

Iodine can increase or decrease thyroid function. Taking iodine together with medications for an overactive thyroid might change the impacts 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 important nutrient. People with access to iodized salt, seafood, and particular veggies are able to get enough iodine from their diet.

In many cases, you might 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.

Speak to your medical professional about your specific iodine needs. [11]


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