Stop fluoridation now: new research on fluoride's brain and thyroid toxicity

Townsend Letter for Doctors and Patients, April, 2005 by Gary Null, Martin Feldman

* A study of workers continuously exposed to fluorine found that 51% had reduced T3 hormone. An analysis of their immune status showed that the T lymphocyte count rose but that the functional activity of the cells declined, indicating an impaired cooperation of immunocytes due to imperfect control under the low T3 concentrations. (53)

* Research found a higher prevalence of goiter (enlargement of the thyroid gland) in two towns in South Africa with high levels of fluoride in the water. (54)

Among animal studies on this topic, an examination of the long-term effects of various doses of iodine and fluoride on the pathogenesis of goiter in mice found that both an iodine deficiency and an iodine excess could induce goiter and other functional and histopathological changes in the thyroid. Fluorine affected the thyroid changes caused by either iodine status. The researchers concluded that iodine and fluorine have mutually interacting effects on goiter in mice. (55) In a study of pregnant and lactating mice who drank fluoridated water, 14-day-old pups had a 75% decrease in plasma free T4 and reductions of 27% and 17%, respectively, in the cerebellar and cerebral protein concentrations. (56)

Countering fluoride toxicity

Research suggests that a number of natural substances may oppose the adverse effects of fluoride by preventing or treating the toxicity. In his editorial in Fluoride, Bruce Spittle notes that dietary factors such as an adequate intake of iodine may protect against high-fluoride effects on the brain and IQ. He adds that while animal studies have found a partial recovery of all parameters studied when sodium fluoride and aluminum chloride are withdrawn, "the administration of ascorbic acid, calcium, or vitamin E, alone or in combination, resulted in a more complete recovery fromm the toxic effects. (57) Recovery was more pronounced with the combination." (58)

Other animal studies have reported similar findings. In one, the effects of sodium fluoride (including locomotor behavioral and dental toxicities) were prevented significantly when the animals received calcium carbonate with the fluoride. (59) In another study, mice receiving a higher concentration of fluoride in drinking water had a remarkable deterioration in learning capability. However, the administration of a proper concentration of selenium with the fluoride could decrease its toxic effects (a concentration of selenium that was too high produced synergistic toxicities). The findings suggested this mineral "might antagonize the neurotoxicity of fluoride on behavior and morphology." (60)

Xylitol: a safe alternative

As research continues to raise questions about fluoride's toxic effects, physicians, dental professionals and consumers may want to seek out other ways to prevent dental decay than by consuming fluoridated water. One alternative with considerable merit is the use of xylitol-containing products. Studies and reviews conducted in the past 10 years have shown that this safe, natural sugar substitute is an effective way to reduce the rate of tooth decay.