According to an estimate more than Two billion people worldwide are at risk for iodine deficiency, caused by low iodine content in soil and groundwater and dietary differences.Over 140 countries have implemented Universal Salt Iodisation (USI) across the globe so far according to WHO Policy. Dr.Wiktoria Tafesse and researchers at the University of Sussex analyzed the impact of a recent mandatory salt iodisation policy implementation in India on literacy and numeracy scores of children in rural India.The investigators found that Iodine fortification of salt increases children’s numeracy and literacy skills by up to 6% thereby strengthening the argument for Universal Salt Iodisation (USI). The study also found that there is a gender difference on the impact of iodine fortification, with improvements seen in girls’ overall reading score but no change of effect found for boys.The study has been presented at the Royal Economic Society annual conference in Brighton.
Medical research shows strong associations between iodine deficiency in utero and early postnatal life and permanently low IQ, and the research suggests that the positive effects of fortification carry into childhood and beyond.
The causal impact of salt iodisation was analysed by comparing the trajectories in the attainment of those children who experienced salt iodisation in early life to those who were too old to benefit from the new Indian iodisation policy, across districts with and without a geographical predisposition to iodine deficiency.
The data revealed that being exposed to the policy in early life improved the likelihood of recognizing simple letters and numbers by up to 6%.
As the children were tested in the home, the changes can’t be attributed to any changes in school policy or attendance and show that the results were not driven by coincidental improvements in health or access to school.
The UK has been identified as a country with mild-to-moderate iodine deficiency in pregnant women. Adequate iodine intake among pregnant women is critical for the brain development of the foetus and thus permanent cognitive attainment of the next generation.
Over 140 countries have implemented Universal Salt Iodisation (USI) across the globe so far, but the UK has not adopted legislation on salt iodisation despite USI being viewed as a simple and cost-effective way to increase iodine levels in the general population.