REVIEW ERS ' CONCLUSIONS Despite most of the included studies being of low quality , the results suggest that iodine supplementation , especially iodised oil , is an effective means of decreasing goitre rates and improving iodine status in children .
Indications of positive effects on physical and mental development and mortality were seen , although results were not always significant .
Adverse effects were generally minor and transient .
BACKGROUND Iodine deficiency is the main cause of potentially preventable mental retardation in childhood , as well as causing goitre and hypothyroidism in people of all ages .
It is still prevalent in large parts of the world .
OBJECTIVES To assess the effects of iodine supplementation overall , and of different forms and dosages of iodine supplementation separately , in the prevention of iodine deficiency disorders in children .
Randomized, double blind, placebo-controlled trial of low dose iodide in endemic goiter.
Iodine ( I ) is essential for normal thyroid function , and the majority of subjects tolerate a wide range of dietary levels . However , a subset of individuals upon exposure to normal or elevated levels of I develop thyroid dysfunction and autoimmunity . In this double blind trial , we evaluated efficacy and tolerability of low dose I in adults with euthyroid , diffuse , endemic goiter . Sixty-two subjects were r and omly assigned I ( 0.2 mg/day ) or placebo for 12 months . After termination of therapy , both groups were followed for a further 6 months . Thyroid sonography and determinations of thyroid-related hormones , urinary I excretion per 24 h , and thyroid antibodies were carried out at baseline and at 3 , 6 , 9 , 12 , 15 , and 18 months . Markedly elevated urinary I values were found during therapy in subjects receiving I ( 32 at baseline vs. 213 micrograms/24 h at 12 months ; P = 0.0001 ) compared to placebo ( 34 and 33 micrograms/24 h , respectively ; P < 0.0001 vs. I ) . I substantially reduced thyroid volume ( 29 vs. 18 mL at 12 months ; -38 % ; P = 0.0001 ) , and at 18 months , the therapeutic effect was sustained . In the placebo group , no significant changes were observed . High microsomal and thyroglobulin autoantibody titers were present in 3 of 31 ( 9.7 % ) subjects receiving I , and I-induced hypo- and hyperthyroidism developed in 2 and 1 , respectively . Fine needle biopsy revealed marked lymphocytic infiltration in all 3 cases . After withdrawal of I , thyroid dysfunctions spontaneously remitted , and antibody titers as well as lymphocytic infiltration decreased markedly . Follow-up of these 3 subjects for an additional 2 yr showed normalization of antibody titers in 2 . Thus , among subjects with endemic goiter , low dose I successfully normalized thyroid volume and body I supplementation ; nevertheless , reversible I-induced thyroid dysfunctions and autoimmunity were observed in nearly 10 % of the subjects
REVIEW ERS ' CONCLUSIONS Despite most of the included studies being of low quality , the results suggest that iodine supplementation , especially iodised oil , is an effective means of decreasing goitre rates and improving iodine status in children .
Indications of positive effects on physical and mental development and mortality were seen , although results were not always significant .
Adverse effects were generally minor and transient .
BACKGROUND Iodine deficiency is the main cause of potentially preventable mental retardation in childhood , as well as causing goitre and hypothyroidism in people of all ages .
It is still prevalent in large parts of the world .
OBJECTIVES To assess the effects of iodine supplementation overall , and of different forms and dosages of iodine supplementation separately , in the prevention of iodine deficiency disorders in children .