| ||From an article Fluoride: A Statement of Concern by Paul Connett, PhD, 2000|
Another line of evidence which indicates that fluoride is an endocrine disrupter is the number of studies that indicate the fluoride may inhibit the functioning of the thyroid gland. Andreas Schuld, president of a group called Parents of Fluoride Poisoned Children, has prepared an excellent summary of the evidence that points in this direction (53, 54). To put the matter as simply as I can, his group has been able to show that areas of endemic fluorosis are also areas designated as being endemic with iodine deficiency disorders (IDD). The group rediscovered studies and documentation from the European medical literature spanning over 30 years of research testifying to fluoride's pharmacological effectiveness in the treatment of hyperthyroidism (the term used to describe an over-functioning thyroid gland). Thyroid hormones are absolutely essential for normal growth and development. Hyperthyroidism means that the thyroid gland is producing too much of the thyroid hormones, T3 and T4. These two hormones have 3 and 4 iodine atoms respectively. Schuld's group has also shown that there is a remarkable similarity between the symptoms listed for hypothyroidism (under active thyroid gland) and those reported for fluoride poisoning (55). Putting these two conditions together, it appears that fluoride decreases the production of thyroid hormones. If you are suffering from hyperthyroidism, fluoride might be of some benefit. But for a normal person if you are exposed to too much fluoride it could result in reducing thyroid hormone production below normal and necessary levels (i.e., hypothyroidism).
It is not clear just how fluoride reduces thyroid hormone production. It may be that fluoride competes with iodine uptake into this gland. Alternatively, fluoride might inhibit the enzymes inside the gland which assemble the hormones from its chemical precursor, the amino acid tyrosine.
Schuld also points to research that fluoride can also stimulate the thyroid glands, which seems contradictory to the discussion above. However, stimulation may not lead to production of the hormones if iodide is in short supply. Such a situation (over stimulation coupled with iodide shortage) might explain the condition known as goiter. Here the gland grows and grows producing a swelling in the neck. The gland grows because it is being stimulated, but because there are no thyroid hormones produced, there is nothing to switch off the stimulating signal. In other words, the normal feedback mechanism is not working. This signal is the hormone (thyrotropin or thyroid stimulating hormone) which is produced by the pituitary gland - the master gland as far as hormonal control is concerned.
53. Schuld, A. (1999). How Do Fluorides Interfere With Thyroid Function. Fluoride Watershed, Journal of the National Pure Water Association, 5, (November), pp. 3-6.
54. Parents of Fluoride Poisoned Children [PFPC] (1999). Comparison of over 150 symptoms and associations: Hypothyroidism/Fluoride Poisoning. PFPC, Vancouver, Canada.
55. Utiger R. (1995). Thyrotropin-Receptor Mutations and Thyroid Dysfunction. The New England Journal of Medicine 332. Website: http://www.nejm.org/content/1995/0332/0003/0183.asp
Also, the damaging effects of bromine (same family as flourine and iodine) on thyroid tissue appears to contribute to the development of auto-immune diseases in the thyroid gland (Hashimoto's thyroiditis). Bromine is routinely added to flour and bread in the US.
Low Melatonin Level
| ||Work from Dr. Jennifer Luke (50-51) indicates that fluoride reaches one very important gland in the body, the pineal gland, at very much higher concentrations than 1 ppm. This small gland is almost at the geometrical center of the brain, between the two hemispheres. However, it is outside the blood brain barrier. It also has a very high supply of blood (a perfusion rate second only to the kidney) and it is a calcifying tissue, laying down crystals of calcium hydroxyapatite like the teeth and the bone. Because of these observations Luke argued that one would expect the pineal gland to concentrate fluoride. When she had the pineal gland from 11 human corpses analyzed she indeed found this to be the case. The levels of fluoride in the apatite crystals averaged about 9,000 ppm (and went as high as 21,000 ppm). The average level is as high as you would expect in the bones of someone afflicted with skeletal fluorosis. The average projected by Luke for the whole tissue was 300 ppm, well over the 1 ppm found to inhibit many enzymes. |
Luke next examined the effect of dosing Mongolian gerbils (the animal of choice for studying the pineal gland) with fluoride. She found that animals fed higher doses of fluoride had a significant decrease in their excretion of melatonin metabolite in their urine. She also found that the high dose fluoride animals took a shorter time to reach puberty. This is exactly what you would expect if melatonin production was lowered. If this result is confirmed by others it would make fluoride an environmental hormone or endocrine disrupter, a topic of intense discussion (52) and review by regulatory agencies in the US and around the world.
50. Luke, J. (1994). Effects of Fluoride on the Physiology of the Pineal Gland. Caries Research, 28, 204.
51. GGVideo [Grassroots and Global Video] (1999). Fluoride, the Pineal Gland and Melatonin: An Interview with and Presentation by Dr. Jennifer Luke. Videotape, length 40 minutes. Available from GGVideo, 82 Judson Street, Canton, NY 13617. Tel: 315-379-9544. Fax: 315-379-0448. E-mail: firstname.lastname@example.org
52. Colborn, T. et al (1996). Our Stolen Future: Are We Threatening Our Fertility, Intelligence, and Survival? Dutton, NY, NY.
| ||It has been suggested that Gilbert's syndrome is due to a partial deficiency of the hepatic enzyme glucuronyl transferase. Fluoride, being an enzyme inhibitor, reduces the enzyme's activity even further.|
John Lee, MD a physician in private practice has stated that elevated bilirubin levels can be reduced in Gilbert's syndrome by avoiding fluoridated water and other sources of fluoride. This physician has seen bilirubin levels rise again when fluoride has been reintroduced. Gilbert's syndrome may be due to a partial deficiency of the hepatic enzyme glucuronyl transferase. Fluoride, being an enzyme inhibitor, reduces the enzymes' activity even further. ["Fluoride Linked to Gilbert's Syndrome", Lee, John R., M.D., Cortlandt Forum, September 1990;101: pp.31-33]
In some cases, complete elimination of fluroide can reverse the jaundice of Gilbert's syndrome.