Controlling the health disorders of iodine : translating geochemistry into health

Iodine, in both deficiency and excess, leads to health problems that affects individuals and communities. Deficiency stunts the development of the fetus and infant, in particular brain and stature [cretinism], with lifelong results. Miscarriages and peri-natal mortality are commoner in deficient communities, which also suffer from a widespread reduction in IQ. An excessive iodine supply in the community contributes to thyrotoxicosis, with potentially fatal effects on the heart, but also on the emotions, metabolism and the digestive system.