Iodine

Iodine is an essential mineral that is found in a large number of foods and is needed by the body for the synthesis of thyroid hormones. It is found naturally in a large number of foods, and is also added to salt, so such salt is called iodized. We can get the recommended daily intake of iodine by eating a variety of foods such as: cod, tuna, seaweed, shrimp, dairy products, eggs. Thyroid hormones are needed for proper bone and brain development in infants, but adequate amounts of iodine are important for everyone, especially babies and pregnant women. Iodine is also available in nutritional supplements, most often in the form of potassium iodide or sodium iodide.

Mostly, people get enough iodine through food and drink, but there are people who have problems with iodine intake because they use non-iodized salt. Pregnant women need about 50% more iodine than other women to ensure a sufficient amount of this supplement for the baby. People on a vegan diet are very often deficient in iodine, as are people who live in regions whose soils are deficient in iodine and consume only local food (mountainous areas (Himalayas, Alps, Andes)). In the body of a healthy person, there is about 10 to 20 mg of iodine, of which 2/3 is found in the thyroid gland, and the rest of this supplement is found in muscles and other tissues.

Daily needs: The optimal daily intake of iodine is from 100 to 200 mcg.

Recommended Dietary Allowances (RDAs) for Iodine

Age	Male	Female	Pregnancy	Lactation
0-6 months	110 mcg	110 mcg
7-12 months	130 mcg	130 mcg
1-3 years	90 mcg	90 mcg
4-8 years	90 mcg	90 mcg
9-13 years	120 mcg	120 mcg
14-18 years	150 mcg	150 mcg	220 mcg	290 mcg
19+ years	150 mcg	150 mcg	220 mcg	290 mcg

Iodine and iodides are absorbed primarily in the small intestine, but also in all other parts of the digestive tract. During absorption, free iodine as well as iodates are converted into iodides. In addition to iodine absorption occurring in the gastrointestinal tract, it can also occur through the skin. About 70% of iodine in the blood is found as part of thyroid hormones, mostly in the form of thyroxine. It is necessary for the thyroid gland to receive about 60 mcg of iodine per day for proper functioning. Iodine is excreted through bile, a smaller part through urine, milk and respiratory tract.

Iodine deficiency: People who do not consume sufficient amounts of iodine cannot synthesize sufficient amounts of thyroid hormone, and this causes many problems. In pregnant women, iodine deficiency can have a negative effect on the fetus, it inhibits the growth and development of the fetus, affects the intellectual function of the baby, as well as sexual development. Minor iodine deficiency can cause a lower than average IQ in infants and children. Goiter, enlargement of the thyroid gland is usually the first sign of iodine deficiency.

In the continuation of the text, we will cite several examples that show how important iodine is to human health:

Development of the fetus and newborn: Women who are pregnant or breastfeeding need to consume sufficient amounts of iodine. It is very important for the proper growth and development of their baby. Breast milk is a good source of iodine, only if the mother consumes a sufficient amount of this supplement through food. However, a large number of studies have shown that mother’s milk does not have sufficient amounts of iodine, so supplementation is indispensable during pregnancy and lactation. The new guidelines recommend that for the proper functioning of the thyroid gland, women who are planning a pregnancy or are pregnant or breastfeeding should take 150mcg of iodine in the form of potassium iodide.
Cognitive functions in childhood: Iodine deficiency in childhood adversely affects the development of the central nervous system. Adding iodine to children with mild deficiency improves their cognitive functions.
Fibrocystic breast disease: Fibrocystic disease is not dangerous, but very often causes lumps and sore breasts. It mainly affects women of reproductive age, but it can also occur in older women, in the menopause period. Iodine can reduce pain and other symptoms of the disease.

Iodine excess: High levels of iodine in the body can show some of the same symptoms as iodine deficiency, including goiter (enlarged thyroid gland). If the concentration of iodine in the body is high for a long period of time, inflammation of the thyroid gland can occur, as well as the development of thyroid cancer. Taking very large doses of iodine can lead to the following symptoms: burning in the mouth, throat, stomach, elevated body temperature, stomach pain, nausea, vomiting, diarrhea, bradycardia.

It is important to emphasize that iodine interacts with a large number of medicines, so you should not take supplements that contain this mineral without the supervision of a doctor or pharmacist. Iodine may interact with metamizole, a drug used to treat hyperthyroidism. Taking potassium iodide with medicines for high blood pressure, ACE inhibitors (lisinopril benazepril, fosinopril), can increase the level of potassium in the blood. Also, blood potassium levels may increase if you take potassium iodide with potassium-sparing diuretics, such as spironolactone and amiloride.

Iodine

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