Impact of iodination on thyroid pathology in Africa.

Thyroid disorders are common worldwide.1 In Africa, dietary iodine deficiency is the major determinant of thyroid pathology, resulting in a spectrum of iodine deficiency disorders, including goitres, hypothyroidism and mental retardation.2 Of these, mental retardation poses the most severe threat to socioeconomic wellbeing; thus, its prevention has been the focus of current global efforts towards sustainable iodine sufficiency.3 At least 350 million Africans are at risk of iodine deficiency.4 According to World Health Organization (WHO) estimates, goitres are present in 28.3% of the African population,4 and approximately 25% of the global burden of iodine deficiency as measured by disability-adjusted life years (DALYs) occurs in Africa.5 The demands of communicable diseases, coupled with the challenges of poverty, civil conflicts and fragile political structures, have in the past frustrated efforts at eliminating iodine deficiency in Africa.6 However, recent decades have seen remarkable improvements in iodine nutrition through salt iodination in the continent.7 The effect of these developments on the pattern of thyroid gland disease are beginning to unravel and will be relevant to the strategies for extending the present gains. In this article, I examine the impact of recent progress in iodine nutrition on the epidemiology of thyroid gland pathology in Africa.