The iron, zinc, and iodine trace elements are essential, which means that your body cannot synthesize them by itself, and you must take them in sufficient quantities with your diet. Your body needs these nutrients for various metabolic processes, however, iodine is only found in some foods. For this reason, it is often added to table salt artificially.
Iodine controls the production of thyroid hormones and is responsible for many metabolic functions. A healthy thyroid benefits childhood growth. In addition, the interaction of iodine with thyroid hormones in the formation of hearing and the brain is indisputable.
The thyroid gland produces pre-hormonal thyroxine (medically called T4) and the active hormone triiodothyronine (T3). The pre-hormone T4 consists of two-thirds of the weight of iodine. Iodine is supplied in alternate doses with food, from the soil, air, or sea. The organs try to get enough iodine in synthesis with the thyroid gland (SDH synthesis).
What is iodine?
Bernard Courtois discovered the trace element iodine. In 1811, during experiments with seaweed steel slag, the Frenchman obtained and collected saltpeter. The saltpeter was used to make black powder for the military.
Only 86 years later, the Nobel Prize winner, Professor Wagner von Jauregg, recommended that the trace element be taken as a preventive measure against goiter and cretinism.
Its name is derived from the ancient Greek word “iodides”, which means violet. Like chlorine, it belongs to the halogen series and has an atomic number of 53 or atomic weight of 127.
In nature, it is only presented in pure form, but as an inorganic salt such as potassium iodide (KJ), sodium iodate or sodium periodate. There are also numerous organic compounds of iodine in algae.
Why do we need iodine?
Iodine is essential for the formation of thyroid hormones. These hormones are needed for various metabolic processes. For example, it is involved in growth, bone-building, and brain development.
Therefore, 70 to 80 percent of the iodine consumed with food is processed in the thyroid. The two most important thyroid hormones are tetraiodothyronine (T4 or thyroxine) and triiodothyronine (T3).
Iodine is transported from the gastrointestinal tract through the blood to the thyroid gland, where it is used for the synthesis of thyroid hormones. These are stored first in the thyroid gland and then released into the blood as needed.
You need it for optimal performance, brain, hearing, physical development, and growth. As well as for the functioning of the body’s immune system, muscles, pituitary gland, and bile.
In medicine, the trace element is used in addition to regulating the thyroid gland, as an X-ray control agent and for disinfection. It is also important for the whole organism, cell growth, and body metabolism.
The body has a hormonal deposit and can keep it for up to 3 months. Excess is excreted in feces and urine. Millions of people worldwide have a deficiency and more than ten percent of them suffer from diseases because of it.
These diseases do not arise only from insufficient intake of iodine through food. In addition, they occur through the consumption of additives that promote goiter in the diet or in drinking water.
How much iodine is needed?
Each adult has a daily iodine requirement of about 200 micrograms (µg). For older people and children, 100 to 180 µg is enough. In contrast, pregnant women and nursing mothers have greater needs.
Environmental influences, the type of diet, or taking medications can also significantly influence your iodine needs. Generally, you should take a little more iodine if you smoke or consume a lot of cabbage, millet, radish, or corn.
What foods are the best iodine suppliers?
Your body cannot manufacture the trace element itself and, therefore, depends on a diet rich in it.
These six foods are large iodine providers for your thyroid health:
Fish is one of the most important food sources to meet your daily needs. The richest in iodine are cod, plaice (flounder), haddock, and coal (stoker). Freshwater fish such as carp and trout contain less iodine.
In the Mediterranean area, you can find algae that are rich in iodine. They contain large amounts of up to 11,000 µg per dry weight and cover or even exceed the daily requirement. Algae also contain calcium, magnesium, and iron.
3. Spinach and green vegetables
Kale, broccoli and spinach are good sources of iodine. 200 grams of spinach a day cover a fifth of the daily requirement.
4. Milk and cheese
Cheese is the favorite among dairy products. It contains 20 to 40 µg of the trace element. In addition to milk, cheese is one of the largest suppliers of iodine, it contains as much as spinach.
5. Peanuts and other types of nuts
Salt is a great source of iodine, but both iodized salt and sea salt can be harmful if you have an overactive thyroid. In this case, be sure to consult a doctor.
Other sources of iodine
It is mainly the sea that provides us with the foods that contain the trace element because sea salt contains a large number of iodine salts. Therefore, sea fish as well as shrimp, lobster, or mussels contain large amounts of this trace element.
In addition, all dairy products also contain iodine, since consciously iodized mineral mixtures have been added to the food.
In contrast, grain products tend to be low in the trace element. When buying bread, for example, make sure it is made with iodized salt.
In case of iodine deficiency, it is recommended to take tablets, but be sure to discuss this with your doctor.
To return to the sea again: algae are also foods that contain a lot of iodine. Some types of algae can provide up to 11,000 µg per gram of dry weight (that’s a good one percent by weight).
In this regard, algae should be consumed with caution, the maximum recommended daily dose of approximately 500 µg and can be exceeded very quickly with them.
The significant and permanent excess of iodine can endanger your health.
The trace element is transported to the thyroid gland and stored there. Your heart rate, blood pressure, the central nervous system need thyroid hormones that work properly.
Bone, fat, and protein metabolism also need iodine-rich nutrition for cell division. This is also important for tissue growth and protein formation.
As soon as iodine deficiency occurs, no process in the body works normally and you get sick. The thyroid enlarges because it wants to produce more hormones and the result is a goiter.
Symptoms of a deficiency
In this case, the thyroid gland is often affected by an enlargement. Less frequently, this results in an underactive thyroid (hypothyroidism).
If an underactive thyroid is very pronounced, the following symptoms appear:
- Fatigue and lack of momentum.
- Increased the need for sleep.
- Disorders in the growth and development of children.
- Pronounced lack of concentration.
- Cold sensitivity.
- Swollen eyelids.
If you notice such symptoms, you should not take tablets on your own, as there could be an allergy or an overactive thyroid (hyperthyroidism). Perhaps another medication is causing a side effect on the thyroid gland.
That is why a clarification with your family doctor is so important.
Hypersensitivity or allergic reactions often manifest as a runny nose, acne, or fever. The voice may seem somewhat hoarse and rough due to swelling (myxedema) of the vocal cords.
Side effects of a deficiency
If there is a deficiency of iodine, not enough thyroid hormones are produced. The consequence of this is fatigue, anxiety, depression, and sleep disorders.
Symptoms range from impaired digestion to increased sensitivity to cold and hair loss to weight gain since the metabolism slows down.
Often, only cysts or larger goiters can be treated with surgery or radiotherapy. This destroys the tissue damaged by iodine. A visit to the doctor is highly recommended because the trigger may be Hashimoto’s autoimmune disease.
Can you overdose?
Due to animal feed, which contains the trace element, you can no longer control iodine intake correctly.
The addition of very large amounts of up to 15,000 µg leads to acute a poisoning.
With an overdose side effects such as cramping, fever and vomiting can occur. A fatal coma is considered the worst side effect that can occur.
With a normal diet or an exact dose, this is very unlikely or almost impossible.
If you have an autoimmune disease, you may need less of this trace element. There is a risk that you may be more sensitive to high iodine intake and in this case, an overdose can be harmful.
Consequences of an overdose
As with a deficiency, an overdose of iodine if it takes place over a longer period of time, has serious health consequences in the form of an overactive thyroid (hyperthyroidism). In addition, hypersensitivity reactions such as rashes may develop.
If the daily intake exceeds 1,000 µg for a longer period, there is talk of an excess, which can cause the following diseases:
- Graves disease.
- Hashimoto’s thyroiditis.
- The Wolff-Chaikoff effect, the thyroid gland blocks any additional iodine intake, resulting in an underactive thyroid.
Iodine supply in children
When children are growing and during puberty, the thyroid needs more iodine. The need increases from four years to thirteen. Therefore, children should consume more of this trace element at this stage.
The development of the child’s performance through a functional thyroid is strengthened and the concentration in learning increases.
The importance of iodine during pregnancy?
Iodine deficiency in a pregnant woman can cause childhood malformations or spontaneous abortions.
The newborn often suffers from congenital hypothyroidism, especially in the early stages of physical development in the womb or in childhood.
Very few thyroid hormones can lead to serious physical and mental deficiencies, sometimes even to cretinism (derived from the French word “crétin”, which can be translated as dumb). In addition, there are other effects such as dwarfism or surprisingly short fingers among others.
Pregnant and breastfeeding women have to provide themselves and their children with the necessary iodine. Therefore, your daily requirement increases to approximately 230 to 260 µg.
To really guarantee this, most pregnant and nursing women are allowed to consume 100 to 150 µg of the trace element in the form of iodine preparations, for example, in tablets, of course, only after consulting the doctor.
It is important to know that iodine-containing medications can cause hypothyroidism in the fetus or infant.