When people think of fluoride being prescribed for medicinal purposes, they generally think of fluoride supplementation to reduce tooth decay. Fluoride, however, has also been prescribed as a drug to reduce the activity of the thyroid gland. Up through the 1950s, doctors in Europe and South America prescribed fluoride to reduce thyroid function in patients with over-active thyroids (hyperthyroidism). (Merck Index 1968). Doctors selected fluoride as a thyroid suppressant based on findings linking fluoride to goitre, and, as predicted, fluoride therapy did reduce thyroid activity in the treated patients. (McClaren 1969; Galletti 1958; May 1937). Moreover, according to clinical research, the fluoride dose capable of reducing thyroid function was notably low — just 2 to 5 mg per day over several months. (Galletti & Joyet 1958). This dose is well within the range (1.6 to 6.6 mg/day) of what individuals living in fluoridated communities are now estimated to receive on a regular basis. (DHHS 1991).
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