The human body needs constant small amounts of iodine for metabolism and brain development, but normal diets in most countries do not contain enough iodine, resulting in iodine deficiency, the world's largest cause of preventable mental impairment. While the health of all population groups can be affected, pregnant women and children are especially at risk. It is also a cause of thyroid disease.

Insufficient iodine intake during pregnancy can lead to lasting brain damage that reduces a child's IQ by 8 to 10 points and up to 13.5 points in case of severe deficiency, hindering children's learning ability and school performance. Adding tiny amounts of iodine to salt for human and animal consumption can address the problem.

The worldwide campaign for Universal Salt Iodisation (USI) was a major public health success that significantly improved the situation and is still the major solution recommended by the World Health Assembly. But not all countries adopted USI, and in addition, progress is slipping due to competing priorities and global events such as the war in Ukraine.

The first Horizon Europe-funded EUthyroid project drew global attention to the situation in Europe, suggesting that up to half of the region's newborns are at risk of iodine deficiency. A 1999 survey identified Europe as having the lowest (27%) coverage of iodised salt of any of the world's regions.

EUthyroid2, as the next Horizon Europe-funded public health research project, aims to target low awareness of iodine-related health risks in children and adolescents, especially young women to ensure the prevention of iodine deficiency in Europe and beyond.

The first EUthyroid consortium's evaluation of iodine deficiency in Europe uncovered major limitations in awareness of the importance of iodine nutrition. EUthyroid2 is a four-year project that will develop best-practice models to inform children, adolescents, and young women, increase their knowledge, and improve their iodine status in order to lay the foundation for their own thyroid and general health and that of their offspring.

Implementation studies and community-based randomised-controlled intervention trials will be conducted in educational and ambulatory-care settings in eight study regions.

EUthyroid2 aims to improve low awareness with respect to iodine deficiency and iodine-deficiency disorders (IDD) and highlight the importance of iodine nutrition among the target groups, including adolescents and young adults, the scientific community, medical professionals, and policymakers.