Iodine deficiency
The addition of iodine to table salt (so-called iodized salt) has largely eliminated the most severe consequences of iodine deficiency in wealthier nations, but deficiency remains a serious public health problem in the developing world. Iodine deficiency is also a problem in certain areas of Europe; in Germany, an estimated one billion dollars in healthcare costs is spent each year in combating and treating iodine deficiency.