Health News - Research finds that schoolchildren have low levels of iodine, which can affect intelligence

Published: 14 April, 2011
by TOM FOOT

SHE was dubbed the “milk snatcher” by her critics after taking free bottles away from schoolchildren in the 1970s.

But could the famously controversial policy of ­former education secretary and prime minister Margaret Thatcher be responsible for a fall in the nation’s IQ?

Royal Free Hospital ­consultant physician and senior endocrinology expert, Dr Mark Vanderpump, has undertaken the first comprehensive research into iodine deficiencies in Britain.

It is a major concern for pregnant women because it causes mental impairment in their children. Babies born to mothers who are deficient typically achieve 10 per cent lower IQs in later life.

Dr Vanderpump has called for a major public health investigation after his findings – following analysis of urine samples from hundreds of teenage girls – were passed to the World Health Organisation (WHO).

He said: “What we found was that we were much more deficient than expected. 

“A cup of milk gives you about half the iodine you need a day. If you’re not drinking milk, as I imagine many schoolgirls do not these days, it may explain the deficiency. When pregnant mothers are iodine-deficient the baby may suffer.”

Dr Vanderpump said that when women went to work in large numbers during the Second World War, the government became aware that many had enlarged thyroids.

“Many countries started to change their salt to the iodine version,” he said.

As a result, a term for iodine-deficient children evolved – “cretinism”. 

Dr Vanderpump added: “Historically, these children were called it in school, but it was banned like other terms. 

“It referred to children of under-active thyroid mums that were very mentally impaired. The government got very worried and insisted every kid had a bottle of milk.”

Before Mrs Thatcher stopped free milk for primary school children, Harold Wilson’s Labour government ended free milk in secondary schools in 1968. 

“Iodine is an important mineral ensuring the thyroid gland controls your metabolism,” said Dr Vanderpump. “It was recognised that the country was probably iodine-deficient around 300 years ago. But then it got into the food chain, because of milk, and basically we thought we were okay.”

The British Thyroid Association research is the first comprehensive analysis of iodine levels across the UK. It found 69 per cent of girls aged 14 to 15 years old were iodine-deficient – 18 per cent had seriously low levels of the mineral in their bloodstream. 

The samples were taken in summer and winter because the iodine in the milk cows produce is higher in the colder months when they are kept indoors and fed artificially, said Dr Vanderpump. 

Camden schools were asked for samples as part of the research – although finding willing schoolgirls was not easy. 

Dr Vanderpump said: “It was difficult to get the girls to contribute. I asked them to try to contribute to science and told them their country needed them. But when I mentioned urine samples to 150 Year 10s I was greeted by 150 ‘urrgghs’! We tried to spread out among the schools; we went to both rich and poor areas.”

He added: “We may have a problem, and we need to look at it further. What are kids having for breakfast? They are probably not having cereal and milk every day. I think there’s something in that.”