Dr Mark Vanderpump
, Consultant Endocrinologist at The Physicians’ Clinic and several colleagues co-published a letter to The Times recently calling on the UK Department of Health to add iodine to the salt used in cooking and for making processed food. Today he was quoted by BBC Health, which reported a new Lancet study showing that mild iodine deficiency in the UK could be causing children to develop less well in terms of their IQ
“We responded to a report in The Times, published on May 1 2013, which expressed concern that iodine deficiency in young people in the UK could be responsible for learning difficulties and literacy problems. This highlighted something we have known since 2011, when I published a study in The Lancet showing that many girls aged 14-15 were lacking iodine
,” he explains.
The study, which looked at the food intake of 737 schoolgirls and measured how much iodine they were excreting in urine, concluded that 51% were mildly iodine deficient, 16% were moderately iodine deficient and 1% had a severe iodine deficiency.
“These girls are now aged 18-19 and over the next 10 years we expect that many of them will be having children. Iodine deficiency in pregnant women increases the risk that their babies will be born with problems that lead on to learning difficulties at school
,” adds Dr Vanderpump.
He and the other experts who signed the letter to The Times recommend a simple solution. “If the government were to agree to add a small amount of iodine to household salt and to the salt used in food manufacturing, the problem could be cheaply and easily solved
How does the UK compare with the rest of the world?
Amazingly, the UK is only one of 32 countries in the world where iodine deficiency is still a widespread problem. Some of the others are Cameroon, Burundi, Afghanistan, Cuba, the Dominican Republic, Ethiopia and Estonia but Denmark, France and Belgium are facing a similar problem to Britain.
Why is iodine deficiency still with us?
Iodine deficiency used to be much more severe and around half of the UK population in the 1920s and 1930s had a visible goitre – swelling of the thyroid gland. This problem was common in other European countries and many decided at that point to add iodine to household salt. The UK did not; iodine has never been added to the salt here.
Instead, the problem was solved accidentally. One of the food groups rich in iodine is dairy products and from the 1940s to the 1980s, successive UK governments provided free or subsidised milk for schoolchildren. This gave them the iodine they needed.
Since the 1980s, free school milk has ended and our diets have changed, with many people eating more processed food, takeaways and fast food, all of which are low in iodine.
What foods contain iodine?
The richest sources of iodine are seafood, so shellfish, fish and seaweed. Other foods that contain reasonable amounts of iodine include:
- Dairy products – milk, eggs, cheese, particularly cottage cheese
- Beans – red kidney, lima, soya, pinto
- Potatoes (if you eat the skin too)