Experts are calling for iodine fortification programmes to be stepped up across Europe after a report identified ‘persistent and increased’ insufficient iodine intake in the region.
A decline in milk and dairy consumption is contributing to the problem, according to the report, which was released last month by the World Health Organization (WHO)/Europe and the Iodine Global Network (IGN).
The authors said the growing popularity of plant-based diets across the region means that consumers are increasingly turning away from these products – which are crucial sources of iodine in many western and central European countries, especially for children.
They called for all salt and plant-based dairy alternatives to be fortified with iodine, highlighting that “much new data has become available, including information about vulnerable population groups” since the last WHO report on the topic was published 15 years ago.
“Overall, lifestyle choices and dietary trends, including more frequent use of processed foods and the switch to plant-based diets and dairy alternatives, are contributing to a persistent, and in some countries an increased, proportion with insufficient iodine intakes,” they wrote.
Iodine is a trace element that is essential for the synthesis of thyroid hormones by the thyroid gland. Intakes vary greatly across the globe: in Asia, where seaweed is a staple of many diets, intakes are very high, whereas in Western countries, deficiency is more common.
Iodine intake is especially important for foetal brain development before and during pregnancy. Iodine deficiency disorders – which can cause goitre, affect reproductive function, and lead to irreversible brain damage among foetuses and infants – are the most common cause of preventable impaired cognitive development, according to the WHO.
Dr Hans Henri P Kluge, WHO regional director for Europe, drew attention to the fact that the health risks associated with iodine deficiency disproportionally affect women.
He said: “The shift towards plant-based dairy alternatives, particularly among women, who already bear a higher risk of iodine deficiency and thyroid diseases than men, is concerning for their iodine nutrition, especially in countries relying on milk as a source of iodine, as most dairy alternatives do not contain it.
“This report has been crucial in highlighting a problem that still exists or is re-emerging in countries in the region.”
Salt iodisation remains the main method for fighting deficiency – but such fortification programmes have also been rendered less effective by population-level dietary and lifestyle changes, the report authors highlighted.
For example, the main sources of salt in Western diets, comprising 70 to 80% of the total, are now foods produced or cooked outside the home, such as bread, processed meats, or ready meals. However, market surveys show that just 9% of the salt in processed food products in Germany and 34% in Switzerland is iodised.
In 24 countries with voluntary or no iodisation programmes, commonly consumed foods are often produced with non-iodised salt.
“Countries need more flexible policy strategies to protect people from iodine deficiency, including mandatory policies for the use of iodised food-grade salt in processed foods and integration of salt reduction and salt iodisation measures,” said Dr Gauden Galea, WHO/Europe strategic adviser to the regional director, Special Initiative on NCDs (noncommunicable diseases) and Innovation (SNI).
“Considering the change in dietary landscapes, there is also a need to ensure appropriate fortification of alternative milk and dairy products with iodine.”
The authors also drew attention to a lack of knowledge among the general public regarding the health risks associated with iodine deficiency.
Dr Werner Schultink, IGN executive director, said: “In addition to these developments, there is a lack of knowledge about the consequences of iodine deficiency among the general public and among health authorities, health professionals, and food producers.
“The result is that progress may be stalling or even declining in some countries. And there are other costs – even mild deficiency, which exists throughout Europe, has a major impact on population health and the economy.”
