Documentation · Labradorader
This page gathers what can be expressed about iodine in numbers: the content of common servings, the recommendations of professional societies by stage of life, the path of the element between the gut and glandular tissue, and the official wording of the three claims authorized for it in the European Union.
Health claims in the European Union cannot be worded freely. Regulation (EC) No 1924/2006 sets the framework, and Regulation (EU) No 432/2012 lists, in an annex, the sentences that may be used. Anyone who wants to use a sentence that does not appear there may not use it — not even if it would be factually correct. This structure explains why the wording sounds so uniform: it is the result of an authorization procedure, not the result of editorial writing.
A common misunderstanding concerns who the authorization applies to. What is approved is always a nutrient, in this case the element iodine, and not a tablet, a powder or a brand. A product may carry the sentence if it contains the prescribed amount of the nutrient; the authorization says nothing about the quality of that product, its manufacture or its price. Two packages with an identical claim can differ in every other respect.
Every authorized claim is tied to a condition. It requires that a food supply at least a certain amount of the nutrient — usually 15 percent of the reference value, per 100 grams, 100 milliliters or one serving. For iodine, the labeling reference value is 150 micrograms per day, so the threshold is around 22.5 micrograms. If it is not reached, the sentence remains inadmissible, however accurate it may be in general.
The reference value itself is not a personal target. It comes from the Food Information Regulation and serves to make percentage figures on packaging comparable. The recommendations of professional societies differ from it, in both directions — the second section returns to this.
The following list gives approximate values for typical serving sizes. They come from nutrition databases and describe averages, not guaranteed contents. The range is striking: a fish dish and a side dish differ by a factor of fifty.
| Food | Serving | Iodine (rounded) |
|---|---|---|
| Haddock, cooked | 150 g | approx. 350 µg |
| Cod, cooked | 150 g | approx. 250 µg |
| Pollock, cooked | 150 g | approx. 200 µg |
| Blue mussels | 100 g | approx. 130 µg |
| Iodized table salt | 1 g | approx. 20 µg |
| Cow's milk | 200 ml | approx. 20 µg |
| Mixed rye bread with iodized salt | 50 g | approx. 10 µg |
| Quark | 100 g | approx. 8 µg |
| Chicken egg | 60 g | approx. 6 µg |
| Potatoes, cooked | 200 g | approx. 6 µg |
Rounding is intentional. Individual measurements vary considerably.
In saltwater fish, the content depends on the species, the fishing area and the preparation; when cooked in water, part of it passes into the liquid, which is usually poured away afterwards. In milk and dairy products, the element does not come from the soil but from the animals' feed and from disinfectants used in milking operations — so the value varies between farms and over the course of the year. In bread and cured meats, on the other hand, the use of iodized salt is a manufacturer's decision that is not always visible on the package.
That is why tables of this kind are useful for comparing orders of magnitude and of only limited use for calculating a personal daily amount.
Alongside the EU labeling value are the estimated values of the German-speaking professional societies. They are graded by age and, for adults, are higher than the value on the package.
| Group | Source of the figure | Value |
|---|---|---|
| Food labeling | EU reference value | 150 µg |
| Children, 4 to 7 years | Estimated value, professional societies | 120 µg |
| Children, 7 to 10 years | Estimated value, professional societies | 140 µg |
| Adolescents, 13 to 18 years | Estimated value, professional societies | 200 µg |
| Adults, 19 to 50 years | Estimated value, professional societies | 200 µg |
| Adults aged 51 and over | Estimated value, professional societies | 180 µg |
| Pregnant women | Estimated value, professional societies | 230 µg |
| Breastfeeding women | Estimated value, professional societies | 260 µg |
Two sets of figures with different purposes: one serves labeling, the other nutrition planning for groups.
From the serving to the site of action there are only a few stations, and none of them is particularly spectacular. What is remarkable, rather, is the tenacity with which the body holds on to an ion that is present in the blood only in tiny concentrations.
The cells of the glandular tissue carry a protein in their membrane that moves iodide together with sodium into the cell interior. The process runs against the concentration gradient and therefore costs energy, which comes from the sodium gradient. In this way the tissue reaches a concentration many times higher than that in blood plasma. The same transport protein is also found, to a lesser extent, in the salivary glands, the stomach lining and the mammary gland.
Inside the gland, the element is bound to a large protein and stored in a viscous mass between the cells. This design allows for a reserve that lasts several weeks — a notable difference from elements whose supply must be replenished daily. When needed, two messenger substances are released from the reserve that differ only in the number of iodine atoms they contain: four in one, three in the other.
The second of the three authorized sentences refers to exactly this tissue. Iodine contributes to the normal function of the thyroid gland — In accordance with Regulation (EU) No 432/2012. It describes the maintenance of a usual state and makes no statement about laboratory values or diseases of this organ.
The two messenger substances leave the glandular tissue via the blood, bound to transport proteins. Only a very small free portion passes into the cells of the target tissues. That is where the part of the process begins to which the first of the three claims refers.
Unlike many hormones, these messenger substances do not dock at the cell surface but at receptors in the cell nucleus that are already bound to specific sections of the genome. When the messenger arrives, the receptor changes its shape and thus its relationship to the surrounding transcription machinery. The result is not an immediate reaction but a changed rate at which certain genes are read — an effect that takes hours to days to show up in the makeup of the cell.
The genes whose transcription rate is influenced in this way include those for enzymes of the respiratory chain and for ion pumps in the cell membrane. Both are major ongoing items in the energy budget. In physiology, the turnover of a tissue is therefore measured by its oxygen consumption: if you know how much oxygen is consumed, you know, to a good approximation, the amount of energy converted, which can be expressed in kilojoules. Iodine contributes to normal energy-yielding metabolism — In accordance with Regulation (EU) No 432/2012.
Nerve cells also carry these receptors in their nucleus. The element itself, however, does not reach them as an ion, but exclusively as a component of the messenger substances that cross the boundary into nerve tissue. There they act on the formation of cell processes, on the sheathing of nerve fibers and on the cells' supply of enzymes. The third sentence rests on this basis: Iodine contributes to normal cognitive function — In accordance with Regulation (EU) No 432/2012. It describes a contribution to a normal function, not an improvement in memory, attention or speed of thinking.
The three sentences in their original wording. They stand on their own and cannot be combined into a broader statement.
Because the Union list is organized by nutrient, not by wording. Several elements have gone through their own scientific opinion on this subject area and therefore carry an identically worded sentence. This means neither that they do the same thing nor that they can replace one another; each entry stands on its own and belongs solely to the element named in it.
No, and that is not an oversight. Statements about diseases are legally excluded for foods, and they would also be inappropriate here from a professional standpoint. The authorized claims are aimed at the general population without a diagnosis. Anyone who knows of or suspects a disease of this organ belongs in the care of a physician.
Applications for the authorization of a claim are submitted by member states, associations or individual companies. They are scientifically assessed, and the Commission then decides whether to include them in the Union list. For this element, that happened with the regulation that came into force in 2012; the underlying scientific opinions date from the years before. The wording has remained unchanged since then.
Neither. The only thing offered is a digital guide to read. There is no shopping cart for supplements, no list of recommendations and no links to retailers. For that reason, we cannot answer questions about a specific product sold in stores.
Through the sale of the paid guide. There is no third-party advertising space on these pages, nor are there sponsored sections or paid mentions. Conversely, ad placements are purchased on other platforms to draw attention to the offering; this does not create any connection to the operators of those platforms.
The purchased file picks up where this page ends: it extends the content tables across six food groups, sets the intake values of European and German-speaking expert bodies side by side in a single overview, and notes the survey year for each value.
One-time access · Digital information product
You can cancel the purchase within fourteen days without giving us a reason. A short message to our contact address is sufficient; no form is required, but the official model form is available. We will refund what you paid using the original payment method. When the period begins and which exceptions the law provides for are set out in the Cancellation Policy.
The texts on this website are general information. They are not medical advice, a diagnosis or instructions for self-treatment, and they do not replace a conversation with a doctor. If you have symptoms or existing medical conditions, are pregnant or breastfeeding, or before taking dietary supplements, please consult a medical practice or a pharmacy. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Dietary supplements are not a substitute for a varied diet and a healthy lifestyle. Do not exceed the daily serving size stated on the package. Keep such products out of the reach of young children.
The publisher of this website is the company named in the Legal Notice. There is no corporate or editorial connection to Google LLC, YouTube LLC or Alphabet Inc. The names Google and YouTube are trademarks of their respective owners; they are mentioned here solely to identify the services concerned. No text on this page has been read, reviewed, approved or endorsed by these companies. Where ad placements from these providers are purchased, this implies nothing about the content of this offering.
We usually respond to reports of errors, questions about a figure or requests concerning your data within two business days.
You can also reach us without the form: [email protected]