According to UNICEF, 14 per cent of 19 19 million babies born every year are at risk of permanent brain damage because of iodine deficiency in pregnancy.
The problem, more common in the developing world, can lead to neurological and psychological problems and reduce a child’s IQ by as much as eight to 10 points, having huge implications for a country’s economic development, a Unicef report warns.
Iodine occurs naturally in the soil but levels are hugely variable around the world.
In 1994 the World Health Organisation and Unicef called on countries to supplement salt with iodine as the safest and most cost-effective way of reducing iodine deficiency.
In a report mapping the extent to which children are at risk from iodine deficiency, Unicef and the Global Alliance for Improved Nutrition say that 86 per cent of households throughout the world have access to iodised salt.
However, the report warns that large gaps remain: in South Asia, 4.3m children are born every year to mothers who have no access to iodised salt and in Eastern and Southern Africa this number stands at 3.9m.
Roland Kupka, senior nutrition specialist at Unicef said that It is impossible to say how many people worldwide have been affected by iodine deficiency. However, he added that 20 countries around the world, including Indonesia, Ethiopia, Bangladesh and Senegal, have documented levels of iodine deficiency in their populations. This compares to 100 in 1990, before the large-scale salt supplementation programme began.
Dr Kupka said that swathes of the population losing IQ points was worrying.
“Children who are born to women who are iodine deficient can lose eight to 10 points of their IQ. When you distribute that at a population level and when you take into account the fact that we are moving towards a knowledge based society that will have tremendous impacts, not only at an individual level but at a society level,” he said.
The report urged countries to implement a range of measures to reduce the risks to unborn children, including identifying at-risk populations and enforcing existing laws on salt iodisation.
Dr Kupka added that this was an easy problem to address.
“It’s entirely within countries’ control to reduce the numbers of babies who are born unprotected against this deficiency,” he said.
The Telegraph is working with the Gates Foundation to raise awareness of global health security.