Worldwide , iodine deficiency affects two billion people and is the leading preventable cause of intellectual and developmental disabilities . According to public health experts , iodisation of salt may be the world 's simplest and most cost-effective measure available to improve health , only costing US$ 0.05 per person per year . At the World Summit for Children in 1990 , a goal was set to eliminate iodine deficiency by 2000 . At that time , 25 % of households consumed iodised salt , a proportion that increased to 66 % by 2006
World Summit for Children
World Summit for Children
Iodised salt