Green tea has emerged as a major natural substance in fighting diseases like heart disease, cancer and helping with weight loss. It’s been mass marketed to billions around the world and many sip it religiously everyday in the hopes that it will make them healthier. All except for one thing, it contains toxic sodium fluoride.
A study in the January 2005 issue of the Journal of American Medicine also found that instant teas appear to contain excessive levels of sodium fluoride. Green tea is one of the worst culprits having double the amount of fluoride as black tea. Brick tea has the highest fluoride concentration and symptoms of fluorosis have been seen in Tibetan children and adults who drink large amounts of this kind of tea.
Tea plants accumulate fluoride in their leaves over time, so the oldest leaves contain the most fluoride, while the youngest contain the least. Therefore, white tea (which is made from youngest leaves and buds) is your best bet to reduce fluoride exposure.
In another study in Caries Research (1996) 30:88-92 Fluoride content in caffeinated, decaffeinated and herbal teas, the average fluoride concentration of infusions prepared from decaffeinated (green & black) tea were found to be 3.19 ppm and ranged from 1.01 to 5.20. This was unexpectedly higher than caffeinated tea and such a difference was statistically significant in this study. It is thought that this is due to the high fluoride content in the water involved in the de-caffeination process, which then would also make coffee similarly decaffeinated high in fluoride content.