'''Fluoride''' (F<sup>-</sup>) is the mildly [[toxic]] [[ion]]ic form of the element [[fluorine]]. It is a common additive to [[toothpaste]], [[mouthwash]], and [[water]] throughout the developed world. It is commonly thought to work to prevent [[tooth decay]].
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'''Fluoride''' (F<sup>-</sup>) is the mildly [[toxic]] [[ion]]ic form of the element [[fluorine]]. It is a common additive to [[toothpaste]], [[mouthwash]], and city [[water]] throughout the developed world. It is commonly thought to work to prevent [[tooth decay]].
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It is believed by many to help harden teeth, although some research has shown the opposite effect. Unfortunately, fluoride also strongly attracts aluminum, which is known to cause [[Alzheimer's disease]].