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Iodine: How to get it, why to get it, and what it does

Freelance journalist
Carina is a freelance journalist. She writes about food and for our "healthy lifestyle" column.

How often do you think about your daily iodine intake? It’s worth doing! This essential trace element serves an important function in our bodies. Find out here how it affects the thyroid gland and how you can make sure you’re getting the right amount. 

What is iodine?

Iodine is one of the many important building blocks that are vital for our health to ensure that everything runs smoothly. More precisely, it’s an essential and naturally occurring trace element that the body cannot produce itself. Small reminder while we’re at it: Trace elements are nutrients that the body needs only in small amounts, unlike essential minerals, which we need more of.

Our tip: In the mood for a natural and healthy snack for in-between meals? Then try our Nuts & Berries mix, which is not only delicious, but also provides you with important nutrients such as vitamins, minerals, and trace elements.

nuts and berries, which contain iodine
Snack on some Nuts and Berries

How iodine functions in the body

Just how essential iodine is becomes clear when you take a look at its effects on the human body. Primarily, as an elementary component of thyroid hormones, it’s involved in the body’s ability to regulate temperature and in growth and maturation, particularly of bone and brain development. It also plays a role in energy metabolism, maintenance of normal skin and nervous system health, and normal cognitive function.

It’s important to remember that iodine helps maintain a healthy system, rather than improve it. With that in mind, it’s not the case that a higher iodine intake is always better. In fact, quite the opposite is true! Further information about daily requirements and overdose risks will be outlined later.

Iodine’s effect on the thyroid gland

Iodine plays a crucial role in the normal functioning of the thyroid gland because it’s one of the building blocks of the thyroid hormones that regulate metabolic processes, stimulate body and organ growth, and control many other processes in the body.

By the way, when we eat foods containing iodine, it makes its way into the blood via the gastrointestinal tract and finds its way into the thyroid gland from there. Up to 80% of the iodine we take in is used by the thyroid.

Iodine during pregnancy and while nursing

Sufficient iodine intake is particularly emphasized during pregnancy and lactation as more is required during these periods than normal. According to the Food Federation Germany, this is for two reasons: First, during this time, the gestating parent’s own thyroid hormone requirements increase significantly, and second, a growing baby must have its own hormonal needs met by its parent (via milk).

According to the German Nutrition Society (DGE), the recommended iodine intake for pregnant people in Germany and Austria is 230 micrograms per day, and as much as 260 micrograms per day when nursing. For the health of the parent and the child, it’s of great importance to prevent an iodine deficiency at all costs. An iodine deficiency could lead to functional and developmental disorders, among other health problems, in the child.

Since pregnant or nursing people usually do not consume enough iodine despite a balanced diet, many rely on dietary iodine supplements to reach their recommended dose. In this case, however, it’s essential to consult a doctor beforehand.

Dietary iodine

As we’ve mentioned, the human body cannot produce iodine on its own and, on top of that, it can only store a limited amount of it, which is why this trace element has to come from somewhere else. Cue our diet as we think of ways to best consume it. But which foods are great sources of iodine?

A bowl of creamy noodles with salmon seen from above, with a cloth napkin next to it

Hier geht’s zum Lachs Rezept

If you’re looking for iodine, there’s plenty of it in fish like plaice, pollock, haddock, and fried herring, as well as in other seafood, but it is also found in milk and dairy products – and in all products made with iodized salt. It’s worth taking a look at the list of ingredients! Seasoning your dishes with iodized salt is an easy way to get it in. But be careful not to exceed the guideline value for daily salt intake according to the German Nutrition Society (DGE).

Did you know that the iodine content of different foods depends on the iodine content of the agricultural soil? Especially in Central Europe, soils are rather poor in iodine due to leaching during the ice age. As a result, the iodine content of the food grown there may have low iodine levels. Thanks to the use of iodized salt, however, Germany is no longer an iodine-deficient region.

Iodine daily requirements and overdose

This brings us to the next point: daily requirements. The German Society for Nutrition guideline values are: for adolescents and adults between 13 and 50 years old, iodine intake should be approximately 200 micrograms per day. Those over 51 should get 180 micrograms a day. For children and infants, the estimated values vary.

As reported by the German Federal Institute for Risk Assessment (BfR), one should not exceed an intake of 500 micrograms a day – in this range, iodine is still considered safe. Anyone who eats a “normal” and balanced diet is unlikely to exceed this amount. Should an overdose occur, however, it can lead to clinical conditions such as hyperthyroidism, the autoimmune disease Graves’ disease, or Hashimoto’s thyroiditis.

Possible consequences of an iodine deficiency

As far as the availability of iodine is concerned, Germany is no longer considered a deficiency zone, but according to the BfR, about 30 percent of people still don’t meet the recommended average requirement for this important trace element.

But what exactly would a lack of iodine look like? In the long term, too little thyroid hormone would be produced as a result, which in turn would lead to thyroid gland enlargement and the formation of what’s known as a goiter. Depending on the case, this may be subtle and invisible to the naked eye, but in extreme cases it can lead to significant swelling of the neck. A long-term deficiency may well have serious health consequences.

Iodine deficiency can lead to symptoms such as fatigue, listlessness, sleep disturbances, drowsiness, feeling cold, reduced performance, and digestive problems, but also a feeling of tightness and pressure in the throat, as well as breathing and swallowing difficulties.

Iodine: Summary

  • Iodine is an essential trace element and it plays a major role in our bodies’ normal functioning, mainly when it comes to the thyroid gland.
  • It’s necessary for thyroid hormone production, which in turn regulate important metabolic processes in the body.
  • For adults up to 50, a daily iodine intake of 200 micrograms is recommended, but anyone who is pregnant or nursing should consume a larger amount.
  • Foods rich in iodine include fish and seafood.
  • Iodized table salt is also an important source of iodine.
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