http://www.townsendletter.com/Jan_2003/fluoridecontroversy0103.htm Also, http://www.fluoridealert.org/health/thyroid/index.html (link found in Cass flouride post http://www.cassiopaea.org/cass/fluoride.htm)
Effects on the Thyroid System
The supposedly safe fluoride levels in our water may pose a particular danger for any of the millions of people who suffer from thyroid disorders, reports Dr. Connett.46 He explains:
“Earlier in the 20th century, fluoride was prescribed by a number of European doctors to reduce the activity of the thyroid gland for those suffering from hyperthyroidism (overactive thyroid) (Merck Index, 1960, p. 952; Waldbott, et al., 1978, p. 163). With water fluoridation, we are forcing people to drink a thyroid-depressing medication which could serve to promote higher levels of hypothyroidism (underactive thyroid) in the population, and all the subsequent problems related to this disorder….
“It bears noting that according to the Department of Health and Human Services (1991) fluoride exposure in fluoridated communities is estimated to range from 1.58 to 6.6 mg/day, which is a range that actually overlaps the dose (2.3 - 4.5 mg/day) shown to decrease the functioning of the human thyroid (Goletti & Joyet, 1958).47 This is a remarkable fact, and certainly deserves greater attention considering the rampant and increasing problem of hypothyroidism in the United States. (In 1999, the second most prescribed drug of the year was Synthroid, which is a hormone replacement drug used to treat an underactive thyroid.)” More than 20 million people in the US receive treatment for thyroid problems, and many others are thought to go undiagnosed.48 Keep in mind that 1 quart of water fluoridated at 1 ppm contains 1 milligram of fluoride.
Excess fluorine in drinking water was a risk factor for the more rapid development of thyroid pathology in a 1985 study. Water with a raised fluorine content resulted in several thyroid effects in healthy subjects, including an elevated production of thyroid stimulating hormone (TSH) and a decrease in the concentration of T3 hormone, compared with healthy people who drank water with a normal concentration of fluorine.49
An elevated level of TSH reflects an underactivity of the thyroid system. The pituitary gland releases TSH to direct the thyroid to manufacture thyroid hormone, but if the thyroid is sluggish in its response, then the pituitary will release excess TSH (hence, the elevated level) to try to further stimulate thyroid activity.
A 1996 study of 165 aluminum production workers with signs of chronic fluoride intoxication found thyroid abnormalities as well. They included a moderate reduction of the thyroid’s iodine-absorbing function, low T3 hormone with a normal level of T4 hormone, and a slight increase of TSH concentration.50
A study of rats also found that fluoride caused a decrease in the levels of T3 and T4 hormones in plasma, a decrease in the free T4 index, and an increase in the T3-resin uptake ratio.51 In another study in which pregnant and lactating mice received fluoridated water, the pups had a 75% decrease in plasma free T4 at 14 days of age compared with a control group.52 A third study looked at the long-term effects of iodine and fluoride on the pathogenesis of goiters and fluorosis in mice. After 100 days of treatment, the fluoride showed some stimulatory effect on the thyroid in iodine-deficiency conditions and inhibitory effect in iodine-excess conditions.53
http://en.wikipedia.org/wiki/Pituitary_gland
The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea that sits in the small, bony cavity (sella turcica) at the base of the brain. Its posterior lobe is connected to a part of the brain called the hypothalamus via the infundibulum (or stalk), giving rise to the tuberoinfundibular pathway. The posterior lobe is thus derived from neural ectoderm while the anterior lobe is derived from oral ectoderm. The anterior pituitary lobe receives releasing hormones from the hypothalamus via a portal vein system. The pituitary gland secretes hormones regulating a wide variety of bodily activities, including trophic hormones that stimulate other endocrine glands.
http://en.wikipedia.org/wiki/Hypothalamus
The hypothalamus (from Greek ὑποθαλαμος = under the thalamus) is a region of the mammalian brain located below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate certain metabolic processes and other autonomic activities. The hypothalamus links the nervous system to the endocrine system by synthesizing and secreting neurohormones, often called releasing hormones, as needed that control the secretion of hormones from the anterior pituitary gland — among them, gonadotropin-releasing hormone (GnRH). The neurons that secrete GnRH are linked to the limbic system, which is very involved in the control of emotions and sexual activity. The hypothalamus also controls body temperature, hunger and thirst, and circadian cycles.
