Fluctuations in iodine concentration in food have been suggested as one risk factor for the development of feline hyperthyroidism, an epidemic disease first described in 1979. Three international studies have examined iodine concentrations of commercial cat foods. The iodine concentration of 112 commercial cat foods from across the USA was measured, and the daily iodine intake by hypothetical 4.
View Article and Find Full Text PDFWe report the cases of 3 infants with congenital hypothyroidism detected with the use of our newborn screening program, with evidence supporting excess maternal iodine ingestion (12.5 mg/d) as the etiology. Levels of whole blood iodine extracted from their newborn screening specimens were 10 times above mean control levels.
View Article and Find Full Text PDFClin Endocrinol (Oxf)
February 2009
Objective: To measure levels of colostrum iodine, which has not been previously measured, and perchlorate and cotinine (a surrogate for thiocyanate derived from cigarette smoke) in women up to 60 h postpartum. Perchlorate and thiocyanate are environmental inhibitors of iodide transport into the thyroid and lactating breast.
Design: Cross-sectional.
Objectives: To characterize the matched maternal and cord plasma and the amniotic fluid concentrations of iodide in preterm and term human pregnancies.
Methods: Specimens were collected at the delivery of 121 singleton pregnancies (92 at term, 29 preterm) with no pre-existing medical complications. Plasma unbound iodide concentrations were measured by the difference between the protein bound iodine and the total iodine measured spectrophotometrically.
Seaweeds and soy are two commonly eaten foods in Asia. Both have been reported to affect thyroid function, seaweed because of its iodine content and soy because of its goitrogenic effect. Twenty-five healthy postmenopausal women (mean age 58 years) completed a double-blinded randomized crossover study.
View Article and Find Full Text PDFContext: Breastfed infants rely on adequate maternal dietary iodine intake.
Objective: Our objective was to measure breast milk iodine and perchlorate, an inhibitor of iodide transport into the thyroid and potentially into breast milk, in Boston-area women.
Participants: The study included 57 lactating healthy volunteers in the Boston area.
Context: Perchlorate has been detected in U.S. drinking water supplies at levels ranging from 4 to 200 microg/liter as well as in agricultural products.
View Article and Find Full Text PDFDietary seaweeds, common in Asia and in Asian restaurants, have become established as part of popular international cuisine. To understand the possibility for iodine-induced thyroid dysfunction better, we collected samples of the most common dietary seaweeds available from commercial sources in the United States, as well as harvester-provided samples from Canada, Tasmania, and Namibia. Altogether, 12 different species of seaweeds were analyzed for iodine content, and found to range from 16 microg/g (+/-2) in nori (Porphyra tenera) to over 8165 +/- 373 microg/g in one sample of processed kelp granules (a salt substitute) made from Laminaria digitata.
View Article and Find Full Text PDFPerchlorate (ClO(4)(-)) and thiocyanate (SCN(-)) are potent and nitrate (NO(3)(-)) a weak competitive inhibitor of the thyroid sodium-iodide symporter. To determine the effects of long-term, high ClO(4)(-) exposure on thyroid function, we conducted a study of 29 workers employed for at least 1.7 yr (50% over 5.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
July 2004
Dietary iodine is essential for thyroid hormone production. Although U.S.
View Article and Find Full Text PDFA cross-sectional survey of 102 Peace Corps volunteers in Niger, West Africa, in 1998 had previously demonstrated a high rate of thyroid dysfunction and goiter attributable to excess iodine from their water filters. The Peace Corps volunteers were followed-up a mean of 30 wk after they ceased using iodine-based water filtration systems. Goiter was present in 44% of subjects during excess iodine ingestion and in 30% after removal of excess iodine.
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