0925 Iodine deficiency in South Africa

A 2007 WHO report on iodine deficiency in Europe makes the statement that over half that population lives in areas of iodine deficiency, and while iodination of salt has long been recognized and promoted internationally as the solution, European households lagged behind others with only 27% of households consuming iodised salt. This situation has led researchers to continue to study the problem and the potentially devastating effects on brain development, and a recent report in the Journal of Clinical Endocrinology and Metabolism provides preliminary results of a study of maternal iodine supplementation during the first trimester, showing early childhood improvements in the Bayley PDI vs unsupplemented controls. The Bayley MDI was not affected, which is counterintuitive, and that plus the small size of the sample might lead one to disregard the study altogether. But before one does this it is important to acknowledge that South Africa also has its share of iodine-deficient areas and a tremendous amount of work has gone into ameliorating the situation. In 1954, as a result of the efforts of the Goiter Research Committee, optional iodisation of salt was legally introduced at a level of 10-20ppm. This was followed in 1995 by mandatory iodisation at a level of 40-60ppm, and subsequently revised again in 2006 to provide 35-65ppm. These levels are designed to achieve the daily intakes recommended by WHO, UNICEF and the ICCIDD (International Council for Control of Iodine Deficiency Disorders) viz 90μg for 0-5yrs, 120μg for 6-12 yr olds, 150μg for adults and 250μg for pregnant and lactating women. Nowadays the national strategy is driven by the South African IDD Network which includes the Dept of Health, UNICEF, MRC and other stakeholders involved in the elimination of IDD. While iodisation of salt has generally been regarded as successful in this country, a 1998 study showed that deficiency (<100μg/l) was still a problem, occurring in up to 40% of rural school children in several provinces. Home use of iodised salt appears to be low, notably in Limpopo, Mpumalanga and North West Province, with the main reasons being consumption of agricultural salt that is cheaper and not iodised, or repackaging of industrial salt (as used in processed food and is also not iodised) and sold by informal traders. Note that 23 October 2009 is National Iodine Deficiency Disorder Day

Read more:
J Clin Endocrin Metab 2009 epub doi:10.1210/jc.2008-2652
S Afr J Clin Nutr 2008; 21: 8-14
Health Systems Trust: 2000 http://www.healthlink.org.za/healthstats/91/data