Voluntary fortification

The two pre-intervention surveys were conducted to determine the status of urinary iodine levels in a representative sample of Tasmanian primary schoolchildren following more than a decade without regular monitoring. The four post-intervention surveys were conducted to examine the effects on urinary iodine levels following the voluntary fortification of bread with iodine. In addition to the assessment of urinary iodine levels, information on SES and geographical location was collected both pre- and post-intervention. Pre-intervention data on dietary sources of iodine were also collected. 

Following voluntary fortification of bread in Tasmania in October 2001, urinary iodine levels in Tasmania school-children increased in surveys conducted in 2003, 2004, 2005 and 2007. The median UIC was 108pg/I across the four surveys. Using the WHO classifications, median... 

Iodine intervention programs supplying iodi2ed salt are presently available in most European countries, compulsory in some countries and voluntary in others. In Denmark, fortification of salt was prohibited up to 1999. 

The iodine supply has been optimized in the past decade by a voluntary iodine fortification program. 

Figure 119.5 Incidence rates of overt hyperthyroidism before and after iodine fortification (IF) of salt. The incidence rate of hyperthyroidism in Aalborg (moderate ID) and Copenhagen (mild ID) before and after the first 6 years of IF of salt. Basic is the time before IF of salt (1997-1998), 1999-2000 is the period of voluntary IF, 2001-2002 is the early, and 2003-2004 is the late period of mandatory IF. The incidence of hyperthyroidism increased significantly in both subcohorts during the study period. In Aalborg, the increase was more pronounced and came before the increase in Copenhagen. Aalborg baseline vs. voluntary IF, P< 0.001 voluntary IF vs. early mandatory IF, P s 0.001 early vs. late mandatory IF, ns. Copenhagen baseline vs. voluntary IF, ns voluntary IF vs. early mandatory IF, P s 0.001 early vs. late mandatory IF, ns. Statistical significance compared with baseline, P < 0.05 P s 0.01 P s 0.001. Data from Pedersen et al., (2006).

It should be noted that the voluntary program of bread fortification in Tasmania was introduced as an interim measure only. As a result of the re-emergence of iodine deficiency in Austrafia (Gunton et al., 1999 Li et al., 2001, McDonnell et al., 2003, Hynes et al., 2004) and in New Zealand (Thomson et al., 2001, Skeaff et al., 2002, 2003) mandatory fortification of bread with iodized salt is presently being considered by Food Standards Australia New Zealand (FSANZ) (2007). 

Hoey, L., McNulty, H., Askin, N., Dunne, A., Ward, M., Pentieva, K., Strain, J., Molloy, A.M., Flynn, C.A., and Scott, J.M., 2007. Effect of a voluntary food fortification policy on folate, related B vitamin status, and homocysteine in healthy adults. The American Journal of Clinical Nutrition. 86 1405-1413. 

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