Panel 1—Timeline for Combating Iodine Deficiency Diseases in Brazil.
1953	-Enactment of law that mandated the iodination of salt for human consumption in endemic goiter areas.
1955	-First national survey conducted with 86,217 students, which found a goiter prevalence of 20.7% in the country.
1956	-Delimitation of endemic goiter areas, determination of salt iodination in endemic areas, and transfer of iodate imports to the Ministry of Health.
1974	-Determination of the obligation of salt iodization by salt producers, at 10–30 mg/kg of salt, with the supervision of states and municipalities.
1974–1976	-Second national survey with 421,752 schoolchildren, which identified goiter prevalence of 14.1%, and found about 15 million with goiter.
1975	-Establishment of the salt quality and identification standard, creation of the Endemic Goiter Fighting Program, transfer of salt iodization to the Ministry of Health.
1984	-Establishment of sentinel municipalities in several states to periodically monitor endemic goiter levels.
1990	-Third Survey in sentinel municipalities by the National Institute of Food and Nutrition, with 16,803 students, which found a prevalence of goiter ranging from 16.4% to 39.9%.
1994	-Establishment of the National Iodine Deficiency Disorders Control Program and increase of the amount of iodine per kilogram of salt to 40–60 mg of iodine.
1994–1995	-Fourth goiter prevalence survey conducted with 178,774 schoolchildren from 428 sentinel and borderline municipalities. Prevalence of goiter found in mild (19.4%), moderate (3.5%), and severe forms (0.9%).
1999	-Salt iodation returns to the private sector, the amount of iodine per kilogram of salt increases to 40–100 mg, and the Interagency Commission for the Control of Iodine Deficiency Disorders is established in the Ministry of Health.
2000	-Implementation of the Thyromobil Project of the International Council for Control of Iodine Deficiency Disorders (ICCIDD)—current Iodine Global Network (IGN)—in 17 sentinel municipalities in six Brazilian states. Among the 1977 schoolchildren evaluated, the median urinary iodine was 360 μg/L, and the prevalence of goiter was 1.4%. The mean concentration of iodine in salt consumed at home was 48.3 ± 28.9 ppm mg kg−1.
2000	-Implementation of the Pilot Project in the state of Tocantins to monitor the consumption of iodized salt through the action of the State Health Community.
2003	-The amount of iodine per kg of salt is reduced to 20–60 mg.
2005	-Establishment of a new commission to monitor all actions by the federal government to prevent and control IDD in Brazil.
2007	-Establishment of the National Program for the Prevention and Control of IDD (Pro-Iodine) aiming at the elimination of IDD by monitoring the impact of salt iodation on the population’s health, updating the legal parameters of salt iodine levels intended for human consumption, and continuing implementation of information, education, communication, and social mobilization strategies.
2008	-Implementation of the National Survey for the Evaluation of the Impact of Salt Iodization (PNAISAL), with 18,864 students from 1865 schools in 479 Brazilian municipalities.
2014	-From the PNAISAL results, the amount of iodine per kilogram of salt is redefined at 15–45 mg.