Abstract

Prolonged administration of a daily dose of 5-10 mg. of fluoride to patients with hyperthyroidism may cause clinical improvement together with a significant fall in the level of plasma protein-bound iodine and a reduction in the basal metabolic rate. Studies with radioactive fluorine failed to demonstrate any important accumulation of fluorine within the thyroid in vivo. Thyroidal, blood and urinary radioiodine studies suggest that fluorine inhibits the thyroid iodide-concentrating mechanism. Fluorine does not impair the capacity of the gland to synthesize thyroid hormone when there is an abundance of iodide in the blood. However, inhibition of the thyroidal concentrating capacity when the total iodide pool is low will impose a critical limitation of hormonal synthesis, and may explain the therapeutic effect.

• Related Studies :

  • Fluoride caused thyroid endocrine disruption in male zebrafish (Danio rerio)

    Excessive fluoride in natural water ecosystem has the potential to detrimentally affect thyroid endocrine system, but little is known of such effects or underlying mechanisms in fish. In the present study, we evaluated the effects of fluoride on growth performance, thyroid histopathology, thyroid hormone levels, and gene expressions in the

  • [Effects of fluoride on the thyroid morphology and thyroid peroxidase and serum thyroid hormones].

    Objective To observe the effects of fluoride on thyroid morphology,thyroid peroxidase and serum thyroid hormones. Methods One - month ablactating SD rats were randomly divided into three groups:the control group, low-fluoride group, middle-fluoride group, high-fluoride group, fed with water containing different fluoride concentration by adding NaF respectively. Rats were sacrificed after

  • Effect of excessive green tea versus fluoride and caffeine on body weight and serum thyroid hormones in male mice

    Green tea is a worldwide used beverage rich in fluoride and caffeine. To study the effect of excessive green tea intake versus fluoride and caffeine on body weight and serum thyroid hormones in male mice. Also, to confirm the effect of excessive green tea intake on thyroid gland was due

  • Effects of sub-acute fluoride exposure on discrete regions of rat brain associated with thyroid dysfunction: a comparative study

    Objectives: In this present in vivo study, it is intended to examine the effects of fluoride on metabolic functions of four discrete regions of rat brain associated with thyroidal insufficiency. Background: Fluoride contamination in drinking water is a major health issue. Adverse health effects of fluoride include dental and muscle fluorosis,

  • Effects of high iodine and high fluorine on children’s intelligence and thyroid function.

    Objective: Try to find out the effects of high iodine and high fluorine on children’s intelligence and thyroid function. Methods: We selected in Qingyun County the Lidian Primary School, where the iodine and fluorine in the water are relatively high in concentration as the investigative point and Dading Primary School where the iodine and

• Related FAN Content :

  • Fluoride's Impact on Thyroid Hormones

    Up through the 1950s, doctors in Europe and South America prescribed fluoride for this purpose in patients with hyperthyroidism. (Merck Index 1968). Fluoride was selected as a thyroid suppressant based on findings dating back to the mid-19th century that fluoride is a goitrogen (a substance that can cause goiter). When used as

  • Mikhailets (1996): Functional state of thyroid under extended exposure to fluorides

    Abnormalities in the thyroid function characterized by a decreased iodine absorption function of the thyroid, a low level T3 syndrome, and a slight increase of the TSH level are observed in cases of chronic fluorine intoxication in the industrial workers.

  • Fluoride Exposure Aggravates the Impact of Iodine Deficiency

    A consistent body of animal and human research shows that fluoride exposure worsens the impact of an iodine deficiency. Iodine is the basic building block of the T3 and T4 hormones and thus an adequate iodine intake is essential for the proper functioning of the thyroid gland. When iodine intake is inadequate during infancy and

  • NRC (2006): Fluoride's Impact on the Thyroid Gland

    Several lines of information indicate an effect of fluoride exposure on thyroid function. It is difficult to predict exactly what effects on thyroid function are likely at what concentration of fluoride exposure and under what circumstances.

  • Fluoride, Water Hardness, and Endemic Goitre

    Variations in goitre prevalence were found to correlate closely with the fluoride content (p=0-74; P<0-01) and with the hardness (p=0.77; P<0-01) of the water in each village. The effects of fluoride and water hardness seem to be independent.