Iodine nutrition in Brazil: where do we stand? / Iodo nutricional no Brasil: como estamos?

Brazilian legislation, since 1955, failed to achieve its objectives because the issue was not properly addressed: iodized salt was only available in endemic areas, at a low amount of 10 mg Iodine/kg salt. Lack of surveillance and cooperation were common errors. From 1982 to 1992, the INAN distributed potassium iodate to the industry free of charge, but it was abolished in 1991. Only four years later (1995) was a new law enacted effective in determining that all salt for human use should be iodized at levels established by the Health Authorities. During the period comprising 1998 to 2004, excessive iodination of salt (40 to 100 mg/kg) could lead to an increased prevalence of chronic autoimmune thyroiditis and iodine-induced hyperthyroidism. In 2003, the content of iodine/kg of salt was lowered to 20 to 60 mg I/kg salt. A national survey of schoolchildren is currently underway and will indicate the changes required for adequate iodine in salt for human use.

A legislação para corrigir deficiência crônica de iodo no Brasil iniciou-se em 1955. O sal iodado seria distribuído somente em áreas endêmicas de bócio, com dose fixa de 10 mg Iodo/kg de sal. Na década de 1982 a 1992, o Instituto Nacional de Alimentação e Nutrição assumiu o Programa Nacional para a Deficiência Crônica de Iodo e forneceu o iodato de potássio a todos os produtores de sal. Em 1992, o INAN foi dissolvido. Nova legislação foi promulgada em 1995. A Anvisa ficou encarregada de supervisionar o teor de iodo em amostras de sal. No período de 1998 a 2004, o teor de iodo no sal foi elevado para 40 a 100 mg I/kg de sal. O excesso nutricional de iodo na população possivelmente aumentou a prevalência de tireoidite de Hashimoto e hipertireoidismo. Inquérito epidemiológico nacional (PNAISAL) em escolares, em execução, indicará as futuras determinações para a adição de iodo no sal.

Iodine status and goiter prevalence after 40 years of salt iodisation in the Kangra District, India.

Thirty primary schools were selected in district Kangra utilizing the population proportionate to size cluster sampling methodology in the year 2004. A total of 6939 children were included in the study. The clinical examination of the thyroid of each child was conducted. On the spot casual urine sample and salt samples were collected from a 'sub set of' children included in the study. The Total goiter rate (TGR) was found to be 19.8%. The median Urinary iodine excretion level was 200 microg/l and only 64% of the salt samples had the stipulated level of iodine. The findings of the present study revealed that current iodine status of population is adequate, however, TGR showed mild iodine deficiency (chronic) and there is a need of continued monitoring the quality of iodised salt provided to the beneficiaries under the Universal salt iodisation programme in order to achieve the goal of elimination of Iodine deficiency disorders from district Kangra.