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Iodine is an integral component of the thyroid hormonal agents, which are needed for typical development and advancement, particularly of the brain and central nervous system. An absence of iodine in the diet plan is the single most typical cause of avoidable mental retardation worldwide. [1]


Iodine was first discovered by Barnard Courtois, a French chemist in 1811 while extracting potassium and salt from seaweed ash. When he inadvertently 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 circulation

Iodine is never ever discovered in nature uncombined, and it is not focused sufficiently to form independent minerals. It exists in seawater, however moderately, as the iodide ion, I −, to the extent of approximately 50 mg per metric heap (0.0016 ounce per load) of seawater. It is also formed in seaweeds, oysters, and cod livers. Sodium iodate (NaIO3) is consisted of in unrefined Chile saltpetre (sodium nitrate, NaNO3). The body consists of iodine in the substance thyroxine, which is produced in the thyroid gland.

The only naturally taking place isotope of iodine is stable iodine-127. An extremely useful radioactive isotope is iodine-131, which has a half-life of 8 days. It is used in medicine to keep an eye on thyroid gland operating, to deal with goitre and thyroid cancer, and to locate tumours of the brain and of the liver. It is also used in investigations to trace the course of compounds in metabolism. Numerous iodine substances are utilized as contrast mediums in diagnostic radiology. In aqueous service even trace elements of iodine in the existence of starch produce a blue-black colour. [3]

Truths About Iodine

Iodine is an essential element needed for life. It is best known for the vital role it plays in thyroid hormone production in people as well as in all vertebrates. Iodine deficiency can result in severe illness, consisting of goiter (bigger thyroid gland), intellectual disability and cretinism.

As a pure aspect, iodine is a glossy 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 produces a purple vapor. Although it is technically a non-metal, it shows some metallic qualities.

Iodine is categorized as a halogen– a subset of extremely chemically reactive components (Group 17 on the periodic table) that exist in the environment as substances instead of as pure components. The other halogens consist of fluorine (F), chlorine (Cl), bromine (Br) and astatine (At). The term halogen indicates “salt-producing.” When these components respond 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 needed for life. It is best understood for the vital function it plays in thyroid hormonal agent production in humans in addition to in all vertebrates. Iodine shortage can result in serious health issue, including goiter (enlarged thyroid gland), intellectual special needs and cretinism.

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

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

Iodine is the least reactive of the halogens in addition to the most electropositive, implying it tends to lose electrons and form favorable ions during chain reaction. It is likewise the heaviest and the least abundant of the stable halogens. There are 30 known isotopes of iodine, however only one is naturally happening (I-127).

Iodine has numerous commercial applications and can be discovered in a range of pharmaceuticals, disinfectants, inks and dyes, drivers, photography chemicals and animal feed supplements. It plays a particularly prominent function in medicine. For example, iodine compounds are commonly used as decontaminating and wound-cleansing solutions and as internal contrasting agents in imaging strategies such as computed tomography (CT) scans, radiography and fluoroscopy. The radioactive isotope iodine-131 is likewise utilized to treat cancer in the thyroid gland.

Trace element

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

Although iodine is not particularly plentiful, it can be found in trace quantities nearly everywhere: water, soil, rocks, plants, animals and people. Seawater is the biggest reserve of iodine, holding about 34.5 million heaps. However the concentrations are so low– balancing in between 50 to 60 parts per billion (ppb)– that direct extraction is not possible. Rivers include less iodine, at roughly 5 ppb, according to Lenntech Water Treatment Solutions of Denmark.

The majority of the world’s industrial iodine is gotten from salt water (water highly filled in salt) connected with gas wells in Japan and from caliche ore mined in the Atacama Desert of northern Chile. In the United States, iodine is derived from deep well salt water in northern Oklahoma.

Truths in summary

  • Atomic number (variety of protons in the nucleus): 53
  • Atomic sign (on the periodic table of the components): I
  • Atomic weight (typical mass of the atom): 126.90447
  • Density: 4.93 grams per cubic centimeter
  • Phase at room temperature level: Strong
  • 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 component with a various variety of neutrons): 37 recognized isotopes; one stable (I-127)

Who understood?

The very first iodized salt was offered in Michigan in 1924. Before this, many people living along the coasts still got plenty of iodine simply by being near the ocean and the seaside soil. People living additional inland, however, were frequently iodine-deficient, resulting in a higher incidence of goiter. When the connection in between iodine deficiency and goiter was developed, public health officials began looking for methods to relieve the issue– ultimately leading to iodized salt.

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

Photography was the first business use for iodine. In 1839, Louis Daguerre developed a technique for producing images, called daguerreotypes, on thin sheets of metal.

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

Iodine belongs of nuclear fallout, the recurring radioactive material that falls from the sky after a nuclear blast. Individuals in a radioactive area are in threat of inhaling or consuming iodine, which is extremely harmful in large dosages. [4]

Uses of iodine

Iodine is considered an important mineral for our bodies. It’s particularly crucial during pregnancy, and exposure in the womb may even assist prevent certain health conditions later in life.

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

1. Promoting thyroid health

Iodine plays an essential role in thyroid health. Your thyroid gland, which is located at the base of the front of your neck, helps manage hormonal agent production. These hormones manage your metabolism, 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 lead to a condition called hypothyroidism.

Provided the broad availability of iodine in western diets, thyroid health isn’t usually affected by low iodine levels in the United States.

You can get enough iodine from your diet by eating dairy products, fortified foods, and seawater fish. Iodine is also readily available 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, too much iodine can have a negative result on the thyroid gland. That’s why you shouldn’t take iodine supplements without your doctor’s recommendation.

2. Minimizing risk for some goiters

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

Non-cancerous thyroid blemishes (cysts) can likewise trigger thyroid gland enlargement.

In some cases a goiter establishes as a direct reaction 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 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 suggest an unique kind of iodine called radioactive iodine to treat an overactive thyroid gland. Likewise called radioiodine, this medication is taken by mouth. It’s utilized to ruin additional thyroid cells to help reduce excessive quantities of thyroid hormonal agent.

The danger with radioactive iodine is that it can destroy a lot of thyroid cells. This can reduce the quantity of hormone production, causing hypothyroidism. For this reason, radioactive iodine is usually just suggested after anti-thyroid drugs have actually failed.

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

4. Treating thyroid cancer

Radioiodine may also be a possible treatment option for thyroid cancer. It operates in much the same method as hyperthyroid treatment.

When you take radioactive iodine orally, the medication destroys thyroid cells, consisting of malignant ones. It may be used as a treatment following thyroid surgery to make certain all malignant cells have been eliminated from the body.

According to the American Cancer Society, radioactive iodine treatments considerably 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 connected to brain advancement in fetuses. One review found that children whose birth mothers had an iodine deficiency during pregnancy were more likely to mature with lower IQ’s and other intellectual hold-ups.

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 physician about iodine supplementation, particularly if your prenatal vitamin doesn’t have iodine (many do not). Iodine supplements may likewise be required if you lack the mineral.

You’ll also require to continue monitoring your iodine consumption if you’re breastfeeding. The recommended 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 moved by means of breast milk to your nursing baby. This is an essential brain developmental period, so babies require 110 mcg each day until they’ve reached 6 months of age.

6. Improving cognitive function

The exact same neurological advantages of iodine during pregnancy may extend to healthy brain function throughout youth. This likewise consists of a decreased threat of intellectual disability.

It is most likely your kid gets all the iodine they require through their diet, but if you have any concerns about their iodine consumption, talk with their pediatrician.

7. Improving birth weight

Just like brain development, iodine during pregnancy is associated with a healthy birth weight. One research study of pregnant women with goiters found that 400 mg of iodine taken daily for 6 to 8 weeks was handy in remedying goiters related to iodine deficiency. In turn, there was an overall improvement in birth weight in newborns.

While iodine consumption can impact an infant’s birth weight and general development, it is very important to note that the above study concentrated on females in establishing areas who were currently lacking in iron.

Unless your physician has identified you are iodine lacking, taking supplements aren’t likely to impact your infant’s weight at birth. In fact, taking iodine unnecessarily can trigger health issues.

8. May aid deal with fibrocystic breast illness

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

Although there is some promise that iodine might help with fibrocystic breast cysts, you shouldn’t attempt self-treatment. Just take iodine for this condition if your physician specifically recommends it. Otherwise, you could be at risk of adverse effects from iodine toxicity.

9. Decontaminating water

Iodine is just one method of water disinfection. This may be particularly valuable if you don’t have access to potable water due to traveling or effects from a natural catastrophe.

2 percent liquid iodine cast may be contributed to water in five-drop increments per one quart of clear water. If the water is cloudy, add 10 drops per quart.

Iodine tablets might also be used, but the guidelines can vary by maker.

Despite the role iodine can play in disinfecting drinking water, there’s also some concerns that it can increase overall iodine consumption in people and result in unfavorable health impacts. Total iodine consumption shouldn’t exceed 2 mg daily.

10. Protection from nuclear fallout

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

While not completely foolproof, the faster KI is taken, the better the thyroid is thought to be protected in case of this type of emergency situation.

There are serious threats related to KI, including intestinal upset, swelling, and allergy. You’re likewise at increased risk for thyroid disease. Your risk for complications is greater if you already have thyroid illness.

11. Dealing with infections

Iodine can be utilized topically in a liquid type to assist deal with and avoid infections. It works by killing bacteria around moderate cuts and scrapes.

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

Follow directions on the packaging for dosage info, and do not use for more than 10 days unless directed by your doctor. [5]

Tools to improve iodine levels

1. Bear in mind salt

Switching to sea salt is one way to ensure 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 considerable difference in your overall iodine levels therefore this should not be something to count on if you are seeking to incorporate more iodine into your diet plan.

2. Concentrate on iodine-rich foods

Sea veggies like seaweed, dulse, and kelp are a frequently ignored food medication that is loaded with iodine. Kelp’s iodine levels are sky-high, with some ranges having up to 2,984 micrograms it has the greatest iodine content of any sea veggie. Kombu, a particular variety of kelp, has the highest iodine material.

Some other greater sources of iodine consist of:.

  • 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 daily and pregnant ladies 220 mcg each day. If you determine that supplementation is required, deal with your medical professional to determine the best dose for you. [6]

Indications of Shortage and Toxicity


Iodine regulates metabolism, the conversion of energy acquired from food into energy to help cells function and grow. A deficiency of iodine can therefore prevent normal development and development. This is especially dangerous in pregnant women and babies, in which miscarriage, stillbirth, stunted development, and cognitive problems (problems with reading, writing, talking, problem fixing, social skills) can occur. In grownups, an iodine shortage of less than 10-20 mcg a day can result in insufficient thyroid hormonal agent production, called hypothyroidism, which interferes with normal metabolic functions like managing heart rate, body temperature level, and body weight. A swelling or swelling in the neck, called goiter, typically accompanies hypothyroidism. Other indications of hypothyroidism consist of:.

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

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


High iodine consumptions are normally well-tolerated in a lot of healthy individuals and do not cause problems. This has been observed in countries such as Japan and Korea that consume iodine-rich seaweed regularly. But some people with autoimmune thyroid illness or who have a history of persistent iodine deficiency can be conscious receiving additional iodine, causing conditions of iodine shortage like hypothyroidism and goiter. Excess iodine can also lead to excessive thyroid hormone production, triggering hyperthyroidism; indications of this condition are an increased metabolism that promotes weight loss, fast or irregular heartbeat, hand tremors, irritability, tiredness, and sweatiness. Sometimes even just a slight boost in dietary iodine above the RDA can trigger iodine-induced hyperthyroidism in delicate individuals.

Some epidemiologic research studies have shown that high seaweed intakes are associated with an increased threat of specific kinds of thyroid cancer, especially in postmenopausal women, however the specific mechanism is unclear.

Excess iodine intake might come from use of high-dose supplements or eating way too much specific seaweeds and salts that contain iodine. Severe iodine poisoning is rare, however signs consist of fever; stomach discomfort; nausea; throwing up; a burning experience of the mouth, throat, and stomach; and even coma. [2] Kids, infants, the elderly, and those with existing thyroid illness are particularly susceptible to iodine toxicity and iodine-induced hypothyroidism and hyperthyroidism.

Did You Know?

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

Iodine supplements can communicate with specific blood pressure medications and diuretics, consisting of lisinopril, spironolactone, and amiloride, triggering a hazardous buildup of potassium in the blood called hyperkalemia.

Iodine is an active ingredient on the other hand agents that a person might take previously having an X-ray or computed tomography (CT scan). It helps to absorb the rays so that clearer images of the body’s organs can be seen. [7]

Suggested intake

The advised consumption 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 amount of iodine in a food depends upon 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 amount of iodine in the food. Produce from the sea is an excellent source of iodine.

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

Because of this variation, the iodine material in foods is often approximate. [8]

Excessive quantities of iodine can be harmful

Having too much iodine, for instance by means of supplements, can cause a few of the exact same problems as iodine deficiency (such as goitre). The level of iodine considered to be too much, and the signs experienced, can vary from person-to-person, depending upon underlying health conditions.

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


Moderate Interaction.

Beware with this mix.

Amiodarone (Cordarone) interacts with IODINE

Amiodarone consists of iodine. Taking iodine supplements in addition to amiodarone might increase the levels of iodine in the blood. Excessive iodine in the blood can cause negative effects that affect the thyroid.

Lithium connects with IODINE

Big amounts of iodine can decrease thyroid function. Lithium can likewise decrease thyroid function. Taking iodine together with lithium may reduce thyroid function excessive. Do not take large amounts of iodine if you are taking lithium.

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

Iodine can increase or reduce thyroid function. Taking iodine along with medications for an overactive thyroid may change the results of these medications. Do not take iodine supplements if you are taking medications for an overactive thyroid, unless advised by a doctor. [10]


Iodine is an essential nutrient. People with access to iodized salt, seafood, and particular vegetables are able to get enough iodine from their diet plan.

Sometimes, you might need 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 doctor about your particular iodine needs. [11]


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