Goitrogenic Substances

Scott et al. 1982). Thyroid insufficiency can cause considerably plumage changes in chickens. In the Brown Leghorn male, the testes remain small and free of spermatozoa, the comb decreases in size, and the male plumage is lost (Underwood 1981). Iodine deficiency appears rapidly when poultry diets contain goitrogenic substances (McDowell 1992, Kroupova et al. 1997). 

High Intake of Dietary Goitrogens Another confounding factor in the assessment of iodine intake may be environmental goitrogens, substances that interfere with thyroid hormone production or utilization (Gaitan, 1990). Vegetables of the genus Brassica have been considered to... 

In the hypophysis, TSH is probably elaborated in those cells of the anterior hypophysis known as basophils. Partial thyroidectomy and goitrogenic substances induce an enlargement and an increase in number of those cells. 

The incidence of goiter in the United States fell sharply following the introduction of iodized table salt Nevertheless, some residual goiter persists, probably not caused by insufficient iodine intakes, but strongly suggesting causes other than iodine deficiency—such as goitrogens (substances that can cause goiter). 

CAUTION Kohlrabi and other vegetables of the mustard family Crudferae) contain small amounts of goiter-causing (goitrogenic). Substances that may interfere with the utilization of iodine by the thyroid gland. In the quantities normally consumed, this is not a concern. Besides, this effect may be counteracted by the consumption of ample amounts of dietary iodine, a mineral that is abundantly present in iodized salt, ocean fish, seafood, and seaweeds such as kelp. 

The reason why we do not always see the most severe manifestations of iodine deficiency (i.e. the presence of cretinism) in places where iodine intake is very low 2 ig/dl) is related to the absence of other environmental factors. Consequently, in cases of iodine insufficiency, we advocate to test also the presence of thiocyanate which is the principal metabolite of most goitrogenic foodstuffs. Urinary thiocyanate concentrations higher than 1.0 mg/dl are suggestive of the intake of goitrogenic substances.H 12... 

Study of the effect of the goitrogen substances for IDD such as nitrates and thiocarbonates in the food. 

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