[Iodine and thyroid: what a clinic should know].
The World Health Organization considers iodine deficiency as a major worldwide  cause of mental and development diseases, estimating that about 13% of the world  population is affected by diseases caused by iodine deficiency. Iodine is a trace  element necessary for the synthesis of thyroid hormones which, since it cannot  be formed by the organism, must be taken regularly with food. Fish and shellfish  are generally a good source, because the ocean contains a considerable amount  of iodine. On the contrary, plants which grow in iodine-deficient soils are poor  in this element, as well as meat and other animal products fed in plants low in  iodine. Salt is the best way for iodine supplementation. Cooking the food with  iodized salt is a desirable practice because it guarantees the presence of this  element. There are also other methods to provide iodine to the general population,  such as adding iodine to drinking water or taking supplements of iodine. In pregnancy  is recommended iodine supplementation, except in patients with known thyroid disorders.  Iodine is an essential component of thyroid hormones (T4 and T3). Inadequate iodine  intake leads to inadequate thyroid hormone production. The most important consequences  of iodine deficiency, in the general population are goiter and hypothyroidism,  and in the severe cases, mental retardation, cretinism and increased neo-natal  and infant mortality. The International Council for the Control of Iodine Deficiency  Disorders (ICCIDD) formed in 1985, with the only aim of achieving optimal iodine  nutrition in the world, in cooperation with UNICEF and WHO. In Portugal, recent  studies show significant deficiencies in pregnancy and The Portuguese Society  of Endocrinology Diabetes and Metabolism, in partnership with General Directorate  of Health, proposed an iodine supplementation during pregnancy with 150-200µg/day.
Sociedade Portuguesa de Endocrinologia, Diabetes e Metabolismo, Lisboa, Portugal.
Maria
M
Santana Lopes
João
J
Jácome de Castro
Mafalda
M
Marcelino
Maria João
MJ
Oliveira
Francisco
F
Carrilho
Edward
E
Limbert
D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000172:deficiency* / Q000502:physiology; D013959:Thyroid Diseases / Q000209:etiology* / Q000517:prevention & control
D007455:Iodine