nutrient
Iodine
A trace element incorporated into thyroid hormones that regulate metabolism, growth and development.
Iodine is present as iodide, iodate and other chemical forms. Iodised salt and seafood are important sources in some diets, while labels do not always declare naturally occurring iodine.
What it does
The thyroid uses iodine to make thyroxine and triiodothyronine. These hormones act throughout the body, including on energy metabolism and development. Iodine biology is closely tied to thyroid regulation, so excess and inadequate intakes are both context-dependent.
Where it comes from
Fish, dairy, eggs and iodised salt can contribute, but food sources and fortification practices vary across Europe. Sea salt is not automatically iodised, and a label may omit naturally occurring iodine.
Food sources
Per 100 g| Food | Per 100 g | Daily reference |
|---|---|---|
| Whole egg, raw, frozen and pasteurized | 61.6 µg | 41.07% |
| Low-fat milk, 1% and fortified | 36.2 µg | 24.13% |
| Plain whole-milk yogurt | 32.3 µg | 21.53% |
| Salmon | 18.4 µg | 12.27% |
| Atlantic salmon, farmed, raw | 3.24 µg | 2.16% |
Compared with EFSA’s adult reference of 150 µg/day.
About these amounts
These values describe the named food and preparation. A 100 g comparison is not a suggested serving. Small amounts are rounded for display; an unreported amount is not zero.
Healthy European adults. Adequate intake: 150 µg/day. These are population references, not individual targets.
Portions recorded by the source
- Low-fat milk, 1% and fortified: 1 cup (246 g) — 89.05 µg, 59.37% of the daily reference.
The source records and EFSA guidance are linked in References below.
Related topics
Iodine is incorporated into Thyroxine (T4)
The thyroid incorporates iodine into thyroxine (T4), one of the thyroid hormones.
Worth knowing
Fortification varies by place. Iodised salt, dairy, seafood and eggs can contribute iodine, but fortification policy and food iodine content differ across countries and production regions.
A closer look
Thyroid status changes iodine interpretation
Both inadequate and excessive iodine can disturb thyroid regulation in susceptible people. Thyroid disease, pregnancy and medicines therefore change the context of an iodine intake record.
References
Source-checked local draft.
Human editorial review pending.
- NIH Office of Dietary SupplementsIodine: Fact Sheet for Health ProfessionalsChecked 2026-09-05
- European Food Safety AuthorityDietary Reference Values for nutrients: Summary reportChecked 2026-09-05
- U.S. Department of Agriculture, Agricultural Research ServiceFoodData Central Foundation Foods, April 2026 JSON releaseChecked 2026-09-05
- NIH Office of Dietary SupplementsVitamin D: Fact Sheet for Health ProfessionalsChecked 2026-09-05
- USDA Agricultural Research ServiceFoodData CentralChecked 2026-09-04