Iodine

Iodine is an essential trace element that plays a vital role in maintaining the normal functioning of the human body.

It is necessary for the proper functioning of the thyroid gland and the production of the hormones thyroxine (T4) and triiodothyronine (T3).

These hormones regulate numerous vital functions, including metabolism, brain development, temperature balance, and heart rate.

Proper iodine intake is crucial for health throughout life, starting from conception and continuing into old age.

Health Benefits

Mood and cognitive functions. Iodine deficiency in the body can lead to depression and decreased mental abilities, especially in children.

Powerful antioxidant. It helps protect cells from oxidative stress and supports overall health.

Cancer prevention. Some studies show that adequate iodine intake may help reduce the risk of thyroid cancer.

Fighting infections. It activates immune cells and helps combat pathogens, strengthening the body’s defenses.

Interaction with selenium. It is necessary for the absorption of selenium, which is also important for thyroid health.

Daily Requirement and Sources

The daily iodine requirement for an adult is approximately 150 mcg (micrograms), while pregnant and breastfeeding women require an increased amount of about 200-250 mcg.

Children and adolescents need smaller doses, depending on their age.

Sources of iodine include:

• Sea fish and seafood (cod, herring, shrimp)
• Seaweed (kelp)
• Iodized salt
• Dairy products
• Eggs

Iodine can also be added to table salt (iodized salt), making it a popular and accessible source of this nutrient.

For residents of inland regions where iodine levels in food may be lower, it is important to ensure the inclusion of these foods in the diet or the use of iodine-containing dietary supplements.

It is important to note that certain factors, such as smoking and consuming foods with high goitrogens (such as certain types of cabbage and soy), can reduce iodine absorption, so they should be limited.

Possible forms and their learnability

Nutrient forms are listed from best to worst:

Potassium iodide (inorganic iodine). Widely used in supplements and iodized salt. It has high bioavailability, approaching 100%, and effectively replenishes iodine deficiency. However, at high doses, it may cause side effects such as nausea or allergic reactions.

Options on iHerb:

NOW Foods, Potassium Plus Iodine, 180 Tablets

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≈ $10.40

NaturesPlus, Iodine, Potassium Iodide, 150 mcg, 100 Tablets

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≈ $11.86

Iodine caseinate (organic iodine). The connection of iodine with the milk protein casein. This form is characterized by a gradual release of iodine, which reduces the risk of overdose and ensures a prolonged intake of the microelement. Iodine casein is easily absorbed and rarely causes side effects.

Iodine from seaweed (organic iodine). Found in algae such as kelp and fucus. In addition to iodine, they are rich in other beneficial substances. However, the absorption of iodine from algae may be less predictable due to variations in iodine content and the presence of other compounds.

Options on iHerb:

Nutricost, Iodine, 325 mcg, 240 Tablets

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≈ $11.95

Swanson, Scottish Kelp, Made With Organic Sea Kelp, 750 mg, 30 Veggie Capsules

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≈ $12.89

Sodium iodate (inorganic iodine). Used for iodizing salt and in some supplements. It has good stability, but its bioavailability may be lower compared to potassium iodide.

Deficiency and Related Diseases

Diseases related to iodine deficiency include:

• Goiter — enlargement of the thyroid gland, which may be visible and palpable on the neck.
• Hypothyroidism — decreased thyroid function, which can lead to fatigue, weight gain, slowed heart rate, and other symptoms.
• Cretinism — severe mental and physical developmental delay occurring in children whose mothers suffered from iodine deficiency during pregnancy.

Excess and Its Impact on Health

Iodine excess, although less common, can cause a range of negative health effects. This condition is known as iodism or hyperiodemia and can lead to mucosal irritation and gastrointestinal disorders such as nausea, vomiting, and diarrhea.

Long-term intake of high doses of iodine can cause thyrotoxicosis, a condition in which the thyroid gland produces too much thyroxine hormone.

This can lead to rapid heart rate, weight loss, anxiety, and other serious health issues. People predisposed to thyroid diseases should be particularly cautious about their iodine intake.

To prevent excessive iodine intake, it is recommended to maintain a balanced diet and avoid:

• taking iodine-containing medications in large doses without a doctor’s prescription;
• using iodized salt along with other iodine-enriched foods;
• excessive consumption of seaweed or other iodine-rich products.

Myths and Misconceptions about Iodine

The darker the seawater, the more iodine it contains? The iodine content in seawater depends not only on color but also on the ecosystem, so this statement is not always true.

Coffee and tea reduce iodine absorption? Scientific studies do not confirm that coffee or tea significantly affect iodine absorption in the body.

Interesting Facts about Iodine

Discovered in 1811. French chemist Bernard Courtois discovered iodine while processing sea plants with sulfuric acid.

This element got its name from the Greek word “iodes,” which means “violet,” due to its characteristic color when evaporating.

Antiseptic. Iodine solutions, such as povidone-iodine, are often used for disinfecting skin before surgeries and for treating wounds.

High volatility. When heated, iodine evaporates and forms violet vapors, making it unique among other elements.

Various forms of iodine. Iodine can exist in the form of crystals, solutions, and organic compounds, making it versatile in application.