Heres a natural news article that tells you how to Detox fluoride from your body.http://www.naturalnews.com/026605_fluoride_fluorides_detox.html
Though two things worth mentioning
1. The article recommends Tamarind as a detox this is not true. The reason those that eat Tamarind have increased fluoride excretion is because Tamarind has fluoride in it. (The tree absorbs fluoride from the environment and deposits much of it into its fruit)
2.Boron has been proven is scientific studies to increase a persons fluoride excretion via urine. The article says you can use Borax which may be true but I would recommend you take a boron supplement instead.