As an essential component of thyroid hormones, iodine is essential for growth, development and numerous metabolic processes. However, the trace element iodine does not occur naturally in the human body and therefore has to be supplied by food. About 70 percent of the absorbed iodine is consumed in the thyroid, where growth and cell division are controlled. Outside the human body, iodine is used as a disinfectant or X-ray contrast agent.
Iodine in food
Iodine is abundant in sea fish and seafood. In addition, the trace element is in milk and eggs, as well as in all foods that have been spiced in the preparation with iodine salt (eg bread). An adult person has an iodine daily requirement of about 200 micrograms, children about 50 micrograms less. For example, the iodine daily dose for adults is included in
- 48 g haddock
- 76 g salmon
- 104 g of plaice
- 154 g mussel
- 166 g of cod
- 340 g oyster
- 380 g of halibut
- 400 g of tuna
- 1000 g of spinach
- 2100 g rye bread
Recognize iodine deficiency
The lack of iodine intake is widespread. It is estimated that over one billion people worldwide are affected by iodine deficiency. Depending on the presence of iodine in the soil, iodine deficiency is regional. Outwardly visible evidence of iodine deficiency is often a goiter (goiter = enlarged thyroid gland).
Especially severe is the iodine deficiency in newborns and small children. There is a risk of serious, irreversible developmental disorders, including cretinism. In adults, iodine deficiency may manifest as reduced temperature tolerance and severe weight changes.
Prevent a shortage of iodine
To prevent iodine deficiency, the Jodsalzverordnung was issued in Germany in 1989, which allows the trace element iodine in small amounts to add to the conventional table salt. According to the iodine deficiency study group, iodine salt is now used in 85 percent of German households.
Since then, iodine deficiency is relatively rare in Germany - only pregnant women, nursing women, athletes or people with hypothyroidism have an increased need for iodine. This should be covered with a regular consumption of dairy products, sea fish, iodine salt and possibly also iodine tablets.
Iodine: overdose rarely
An iodine overdose or iodine poisoning can hardly arise through a normal diet. One kilo of salt may not be added by law more than 25 milligrams of iodine. An iodine overdose therefore arises more due to the improper consumption of iodine tablets.
People with iodine allergy may also experience the symptoms of iodine overdosage if they eat too much iodine or drink iodine. These manifest in headache, conjunctivitis, gastrointestinal complaints, burning in the mouth and throat and iodine acne.
Iodine and radioactivity
Iodine is basically a natural element and completely harmless. However, nuclear fission produces radioactive iodine-131 and iodine-123. If these isotopes enter the human body, they deposit in the thyroid gland and can cause considerable damage there, in the worst case even thyroid cancer.
Therefore, for example, in a reactor accident iodine tablets are distributed to the population, in which iodine is contained in a high dose, thus protecting the thyroid gland. However, the iodine tablets must be taken as precaution and as quickly as possible, because once the dangerous iodine-131 or iodine-123 once entered the thyroid gland, the tablet can not do anything.