What is iodine?
Iodine is a vital trace element that is urgently needed for the function of the human thyroid gland. It is a central component of thyroid hormones, which mainly regulate energy metabolism.
In addition, they are involved in processes of bone formation, growth and brain development. If there is a prolonged (chronic) iodine deficiency, the thyroid gland enlarges (goiter).
How does iodine work?
Iodine is absorbed through food and metabolized in the thyroid gland. With the iodine provided, the thyroid gland forms both thyroxine (T3) and triiodothyronine (T4) – the two important thyroid hormones.
The finely tuned interaction of both hormones significantly controls the body’s energy metabolism.
If the body produces too few thyroid hormones, there is an underactive thyroid (hypothyroidism). This can have many causes. For example, it can be the result of an autoimmune reaction against the thyroid gland (e.g.: Hashimoto’s thyroiditis), a surgical removal of the thyroid gland or a (chronically) pronounced iodine deficiency.
Depending on the cause, hypothyroidism can also develop insidiously and manifests itself, among other things, in concentration problems or has a negative effect on the psyche.
How much iodine do you need daily?
On average, the body needs about 150 – 200 micrograms of iodine daily to form a sufficient amount of thyroid hormones – however, the actual amount depends on age.
Women who are pregnant or breastfeeding may have an increased iodine requirement. However, the studies on the subject of iodine in pregnancy are not yet clear – clarify any questions about a possible supplementation of iodine in pregnancy in advance with your attending physician.
The German Nutrition Society offers the following orientation for the recommended daily iodine intake:
- Infants and toddlers up to 12 months: 40 – 80 micrograms
- Children up to 10 years: 100 – 140 micrograms
- Children up to 15 years: 180 – 200 micrograms
- Adolescents and adults from 15 to 51 years: 200 micrograms
- Adults from 51 years: 180 micrograms
- Pregnant women: 230 micrograms
- Breastfeeding women: 260 micrograms
What foods contain iodine?
In Germany, however, the iodine content of the soil is low. Consequently, the food produced on it is also generally low in iodine. Depending on the type of soil fertilization, the amount of iodine added to animal feed or the addition of iodized table salt to processed foods, the content can vary greatly.
As a rule, the daily iodine requirement can nowadays be adequately covered by a balanced and conscious diet. Even the sparing, moderate use of iodized table salt can usually effectively prevent a deficiency. However, you should never take (low-dose) iodine tablets available from pharmacies yourself without consulting a doctor! If you suspect that you may have an iodine deficiency, you should definitely have this clarified by a doctor.
What happens in case of iodine deficiency?
However, if the iodine deficiency persists for a long time, it becomes chronic. The body reacts by advancing thyroid growth (goiter). In this way, it tries to produce a larger amount of thyroid hormones. However, this does not succeed in the case of persistent iodine deficiency.
You can find more information about iodine deficiency here.
How does too much iodine manifest itself in the body?
Excessive intake of iodine can be dangerous for certain people. In particular, elderly people or patients with undetected thyroid nodules may develop life-threatening hyperthyroidism if they take too much iodine.
Other applications and the role of iodine in medicine
In medicine, iodine also has other important applications: For example, it is used in radioiodine therapy for thyroid cancer. This involves targeted local irradiation of the thyroid gland by deliberately administered radioactive iodine molecules.
Doctors also use the properties of iodine molecules in diagnostics: since they can influence X-rays, iodine-containing contrast media (e.g.: iodobenzoic acid) are used in certain nuclear medical examination procedures (scintigraphy).
In addition, elemental iodine has a disinfecting effect. It is therefore the main component of Betaisodona – a germicidal antiseptic that supports wound healing.