In 2025, the German Nutrition Society (DGE) published new iodine reference values while simultaneously warning of declining supplies. We explain what this means for you, without exaggeration.
Discover Minerals →According to the reference values from the German Nutrition Society (DGE) valid as of 2025, adults need 150 micrograms of iodine per day, pregnant women need 220 micrograms, and breastfeeding women need 230 micrograms. These figures have actually been lowered compared to previous recommendations; however, the DGE simultaneously warns that actual iodine intake in Germany is declining again, partly because the food industry is using iodized salt less frequently and fewer dairy products are being consumed. This guide explains how iodine deficiency manifests, how much iodine you truly need, and why regulatory authorities are issuing explicit warnings in 2025 and 2026 regarding certain high-dose iodine supplements.
- How does an iodine deficiency manifest?
- How much iodine do you really need? The new 2025 reference values
- Why is iodine supply in Germany declining?
- Who is at particular risk?
- Caution with high-dose iodine supplements: current warnings
- Expert Perspectives & Protocol Breakdown
- Iodine and the thyroid: what else is important
- When is iodine supplementation useful?
- Limits of this guide
- Frequently asked questions
How does an iodine deficiency manifest?
Iodine is a building block of the thyroid hormones T3 and T4, which regulate the energy metabolism of virtually every cell in the body. In the case of a mild to moderate deficiency, the thyroid initially forms more tissue as a compensatory measure, visible as a goiter (struma), before any noticeable discomfort occurs. Possible signs of a more pronounced deficiency include fatigue, difficulty concentrating, sensitivity to cold, dry skin, and weight gain—classic symptoms of impaired thyroid function. These complaints are nonspecific and can have many other causes, which is why an iodine deficiency can only be reliably diagnosed through a medical examination, usually via thyroid levels and, if necessary, iodine excretion in urine.
How much iodine do you really need? The new 2025 reference values
The DGE revised its 2025 iodine reference values in conjunction with the Austrian Nutrition Society and lowered them: from the previous 200 micrograms (under 51 years) and 180 micrograms (51 and older) to a uniform 150 micrograms per day for all adults. The safety margin of the old values, which was intended to compensate for the insufficient supply situation in Germany and Austria, no longer aligns with current methodology for deriving nutrient reference values. Concurrently, in its Opinion No. 065/2025 dated December 19, 2025, the German Federal Institute for Risk Assessment (BfR) recommended limiting the amount of iodine in dietary supplements to a maximum of 100 micrograms per recommended daily portion for adolescents aged 15 and over and adults, and to a maximum of 150 micrograms for pregnant and breastfeeding women.
→ Source: German Nutrition Society (DGE), New reference values for iodine intake – Iodine more important than ever!, Press Release 2025 · Federal Institute for Risk Assessment (BfR), Opinion No. 065/2025, Updating the maximum quantity recommendations for iodine in food, including dietary supplements (December 19, 2025)
| Group | Reference Value 2025 (DGE) | Recommended Max. Supplement Dosage (BfR) |
|---|---|---|
| Adults (15+ yrs.) | 150 µg / day | max. 100 µg / daily portion |
| Pregnant women | 220 µg / day | max. 150 µg / daily portion |
| Breastfeeding women | 230 µg / day | max. 150 µg / daily portion |
Reference values: DGE 2025. Maximum quantities for dietary supplements: BfR Opinion No. 065/2025 (recommendation, no legal upper limit).
Why is iodine supply in Germany declining?
By nature, Germany is an iodine-deficient region because the soil contains little iodine, and since the 1980s, supply has largely been maintained through iodized table salt in bread, meat products, and processed foods. According to the Consumer Association, however, the food industry is now opting for iodized salt less frequently, while more people are eating plant-based alternatives instead of milk and dairy products, which traditionally also provide iodine. In its opinion from December 2025, the BfR cites precisely these changing dietary habits as a reason for the persistent inadequate iodine supply of large segments of the population.
→ Source: Consumer Association, Iodine supply is declining again in Germany
No dietary supplement is approved in the EU for the treatment of a diagnosed iodine deficiency. A confirmed deficiency belongs under medical care, where appropriately dosed pharmaceuticals are available.
Who is at particular risk?
Pregnant and breastfeeding women are at particular risk because demand increases significantly due to thyroid hormone production for the unborn or breastfed child; a deficiency during this time can impair the child's brain development. Vegans also have an increased risk because fish and dairy products—two important natural sources of iodine—are omitted. You can find more on this and other critical nutrients in vegan diets in our Vitamin B12 Deficiency Guide. Anyone who generally eats little iodized table salt, saltwater fish, or dairy products should, if in doubt, have their own levels checked by a doctor before resorting to a supplement.
Caution with high-dose iodine supplements: current warnings
Because the supply situation is strained, some people are turning to heavily overdosed products that regulatory authorities in 2026 explicitly classify as risky. In a market check of 14 online offers, the North Rhine-Westphalia Consumer Association warned against so-called Lugol's solution, a preparation originally developed as a disinfectant that is falsely being offered online as an iodine dietary supplement. The Consumer Association also warns against seaweed products such as kelp capsules, which can contain highly fluctuating and excessive levels of iodine, which is why the BfR proposed binding maximum iodine levels and labeling requirements for algae products in 2026.
→ Source: Consumer Association NRW, Disinfectants not suitable for iodine supply – Market check of 14 online offers for Lugol's solution, 2026 · Federal Institute for Risk Assessment (BfR), Binding maximum iodine levels in algae can help reduce health-hazardous intake levels, 2026
⚠️ A single drop (0.05 ml) of a five-percent Lugol's solution already contains about 6.3 milligrams of iodine, which corresponds to approximately 42 times the recommended daily requirement for an adult of 150 micrograms. Lugol's solution is not a dietary supplement, but a historical disinfectant.
Expert Perspectives & Protocol Breakdown
The BfR follows a quantitative risk assessment approach: based on consumption data, physiological requirements, and toxicological thresholds, it derives concrete numerical values, such as the recommended maximum dietary supplement dosage of 100 micrograms of iodine per daily portion for adults or the requested binding maximum levels for iodine in algae products. This work is preventive and model-based—it estimates which intake levels are safe on average for the population before concrete damage occurs.
→ Source: Federal Institute for Risk Assessment (BfR), Opinion No. 065/2025 (December 19, 2025)
The NRW Consumer Association, conversely, follows an empirical market-check approach: instead of deriving threshold values, it purchases and tests real products sold online—in this case, 14 concrete offers of Lugol's solution—and uncovers that a historical disinfectant is being falsely marketed as an iodine dietary supplement, with an iodine amount that contains 42 times the recommended daily requirement in a single drop. For consumers, the comparison means: the BfR says how much iodine is safe in principle; the Consumer Association shows which specific products on the market are already exceeding these limits.
→ Source: Consumer Association NRW, Disinfectant not suitable for iodine supply, 2026
Iodine and the thyroid: what else is important
Iodine is just one of several micronutrients that the thyroid requires for normal hormone production; selenium also plays a role, including in protecting thyroid tissue and in the conversion of hormones. Both trace elements should not be viewed independently of one another; you can find more on the study situation regarding selenium in our selenium study check. Important for everyone with a diagnosed thyroid condition: In 2026, the German Society for Endocrinology expressly warned against nutritional supplements advertised on the internet that allegedly support thyroid function or the conversion of T4 to T3, for example with choline or milk thistle extracts. According to the professional society, there is a lack of evidence for such health claims, and individual ingredients can even interfere with existing L-thyroxine therapy. Anyone already undergoing treatment should therefore coordinate any additional preparation, including iodine, with their attending practice beforehand.
When is iodine supplementation useful?
Nutrition comes first: Iodized table salt used in cooking, saltwater fish once or twice a week, and dairy products cover a large part of the requirement for most people. Targeted supplementation can make sense if these sources are consistently missing, such as in a vegan diet, or if there is an increased need, such as during pregnancy and breastfeeding. In these cases, professional societies recommend preparations within the aforementioned maximum amounts, not the frequently overdosed products from the section on current warnings. For existing thyroid conditions or uncertainty about your own intake, medical clarification, if necessary with determination of iodine excretion in the urine, is the safer first step before any supplementation.
Limits of this guide
This article does not replace a medical diagnosis or individual nutritional counseling. Both an unrecognized iodine deficiency and iodine overdose can burden the thyroid, which is why blanket dosage recommendations without knowledge of the individual situation are not serious. People with known thyroid conditions, pregnant women, nursing mothers, and individuals already taking iodine-containing medication should always clarify the intake of additional iodine supplements with a doctor beforehand.
Frequently asked questions
How much iodine do I need per day?
According to the DGE reference values revised in 2025, the daily requirement for adults is 150 micrograms, for pregnant women 220 micrograms, and for nursing mothers 230 micrograms.
How can I tell if I have an iodine deficiency?
Possible signs include a visibly enlarged thyroid (goiter), fatigue, poor concentration, sensitivity to cold, and dry skin. These symptoms are non-specific; an iodine deficiency can only be reliably determined by a doctor via thyroid values.
Is Lugol's solution suitable for iodine supply?
No. The Consumer Association NRW expressly warns against it: A single drop already contains about 42 times the recommended daily requirement and can endanger the thyroid. Lugol's solution was originally developed as a disinfectant, not as a nutritional supplement.
Are algae supplements a safe source of iodine?
Not reliably. The iodine content in seaweed like kelp fluctuates significantly and is often much higher than stated. The BfR therefore proposed binding maximum iodine levels and clear labeling requirements for algae products in 2026.
Who should be particularly careful before taking iodine supplements?
People with known thyroid conditions, especially those on L-thyroxine therapy. In 2026, the German Society for Endocrinology warned against advertised thyroid nutritional supplements without sufficient evidence that can interfere with existing therapies.
Why is the iodine supply in Germany declining, even though the reference values have been lowered?
According to the Consumer Association, the food industry is using iodized salt less frequently again, while at the same time more plant-based substitutes are being eaten instead of dairy products. Both have traditionally been important sources of iodine in Germany.
References & Scientific Citations
- German Nutrition Society (2025). New reference values for iodine intake – Iodine more important than ever!
- German Nutrition Society. Reference values for nutrient intake – Iodine
- German Federal Institute for Risk Assessment (2025). Statement No. 065/2025, Update of the maximum limit proposals for iodine in food, including dietary supplements (December 19, 2025)
- German Federal Institute for Risk Assessment (2026). Binding maximum iodine levels in algae can help reduce health-hazardous intake levels
- Consumer Association NRW (2026). Disinfectants not suitable for iodine supply
- Consumer Association. Iodine supply is declining in Germany again
- German Society for Endocrinology (2026). Caution regarding internet advertising: DGE warns against nutritional supplements for thyroid patients
Find the right nutritional support
Lab-tested mineral and vitamin supplements, made in Germany. In case of existing conditions, speak with your doctor beforehand.
View now →
