Environmental controls on iodine deficiency disorders (IDD)

It is estimated that in excess of one billion people world-wide are at risk from iodine deficiency disorders (IDD), the most obvious manifestation of which is goitre (see Fordyce, 2000). Iodine deficiency is the world’s most common cause of mental retardation and brain damage, and the negative effects of impaired mental function have a significant impact on the social and economic development of communities. Although IDD can be caused by a number of factors, goitrogens for example are substances that interfere with the correct functioning of the thyroid gland; the simple cause in rural selfsufficient communities is a lack of iodine in the environment.