Salt iodization change

We will analyze those thyroid cancers that were shown to have undergone changes in their incidence after the implementation of iodine prophylaxis in different endemic goiter areas, probably through the effect of dietary iodine in relation to serum thyrotropin (TSH) levels and increase of thyroiditis, as well as in relation to the standard of medical care. We will also focus on the effect of salt iodization... 

This huge multicenter trial demonstrated that there was an increase of hyperthyroidism after the elevation of salt iodization with the highest RR in 1992. For oHTA the incidence increased from 30.5/100000/year in 1987 to 41.7/100000/ in 1992 and decreased to baseline incidence in 1995. In contrast, the incidence of oHGD doubled from 1987 (incidence 10.4/100,000/year) to 1993 (20.9/100,000/ year) and was still high in 1995 (18.0/100000/year). From this study, it can be concluded that increase in iodine supply (change from IDA to ISA) leads to a transient increase, followed by a decrease, in thyroid autonomy, but to a permanent increase in Graves disease. 

Table 84.3 Changes of the ratio of papillary to follicular thyroid cancer in Austria from 1952 to 1995 due to salt iodization...

Hofstatter (1980) could demonstrate that the ratio of papillary to follicular thyroid cancer changed from 0.2 to 1.1 before and after the first introduction of salt iodization in 1963. We investigated the influence of the elevation in salt iodization to 20 mg Kl/kg salt on the histological types of DTC. Gomez-Segovia et al. (2004) found that, in the period from 1985 to 1989, the ratio was 2.6 and increased to 4.0 between 1990 and 1995. 

Notes Changes in the parameters of iodine kinetics in the National Capital Territory of Delhi with time after salt iodization showed a decrease in thyroid iodine clearance with an increase in urinary and plasma iodine levels. Values are expressed as geometric mean (standard error). 

In view of changing eating patterns (vegetarians and reduced salt intake) and lack of universal salt iodization, screening of pregnant women would help to identify those who are at maximum risk. 

Changes in Brazilian legislation relative to salt iodization... 

In 2003, after the publication of the results of the Thyromobil Project (2001) relative to excessive iodine found in urine, ANVISA changed the recommendation on iodine content for human consumption, lowering it to iodine of 20-60 mg/kg of salt, which remains valid to date (Brasil, 2003). Table 124.5 shows an overview of the Brazilian legislation on salt iodization. 

Mali is a landlocked country in West Africa, and is one of the poorest countries in the world. Iodine deficiency disorders (IDD) have been prevalent in several areas of the country, especially in the southern part. This chapter provides a historic overview of the changes in IDD over time, and of the various strategies that have been implemented to combat IDD. While the national total goiter rate was estimated to be 30% in 1974, a nationwide survey in 2005 found a total goiter rate of 8%, with 88% of the households using iodized salt. The latest figures indicate that Mali still suffers from iodine deficiency, and that efforts must continue in order to reach the goal of universal salt iodization. 

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