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Fluoride stays in the body and over time will calcify the pineal gland, which is a poorly understood part of the body.

Fluoride was used in the past to pacify populations, at least, that is the claim made by anti-F people (I haven't myself run down the sources).

There are books out concerning F and its effect on the body's metabolism, such as this one http://www.amazon.com/Fluoride-Aging-Factor-Recognize-Devast... .

Too much fluoride can lead to fluorosis - there is this case of fluorosis among horses drinking municipal water that was fluoridated http://www.fluorideresearch.org/391/files/3913-10.pdf .

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