Mild iodine deficiency and thyroid disorders in Hong Kong.

OBJECTIVES To review evidence of iodine deficiency and clinical thyroid disorders in Hong Kong. DATA SOURCES Publications on local dietary iodine intake, the iodine content of local food items, and clinical thyroid problems in the Hong Kong population. DATA EXTRACTION Data was extracted and evaluated independently by the authors. DATA SYNTHESIS Iodine is an essential nutrient. Iodine deficiency can lead to goitre, hypothyroidism, mental deficiency, and impaired growth. It is now appreciated that determination of goitre incidence in children alone may grossly underestimate the problem of iodine deficiency in a population. In total, the evidence indicates that iodine deficiency exists in Hong Kong, leading to clinical problems of transient neonatal hypothyroidism, goitrogenesis, and thyroid disorders in pregnant women and neonates, as well as thyroid dysfunction in the elderly. CONCLUSION A supplementation programme aimed at a relatively uniform iodine intake is recommended to avoid deficient or excessive iodine intake in subpopulations.