Okay, enough is enough. Over the last few years, I've said that we shouldn't eat sugar, baked goods and pasta, omega 6 vegetable oils, boxed cereals and crackers, store-bought salad dressings, processed foods, soy, low-fat or no-fat milk, (pasteurized dairy or pasteurized anything including fruit juice for that matter), grain-fed factory-farmed meat, poultry and eggs, and well, I can handle that most of the time. But tea??? I love my cup of tea. Is NOTHING sacred? Heavy sigh. Tea leaves seem to accumulate more fluoride from the soil and from the air than any other plant that we eat, and because pollution has increased over the last decades, fluoride in tea is increasing as well.
Green tea in particular is heavily promoted as being a very healthy beverage because of the anti-oxidants it contains. But it turns out that the fluoride levels in tea are higher than the Maximum Contaminant Level (MCL) set for fluoride in drinking water, which is 1mg/L. Double-blind studies exist proving the adverse health affects of fluoride at the level of 1ppm in water, and there are no studies documenting safety of ingesting fluoride at any level. No studies seem to exist investigating the effects of fluorides on the anti-oxidants in green tea, although other studies involving antioxidants show that they are adversely affected by fluoride. A 6oz cup of green or black tea seems to contain between 1.3 and 7.8mg/L of fluoride, so possibly about 8 times the suggested safe dose, and I'm sure I'm not the only one that has more than one cup of tea per day.
Fluoride may be a big culprit in hypothyroid (sluggish thyroid), as fluoride has a bigger affinity to the iodine receptor than iodine does, and the thyroid needs iodine to function properly. Fluoride was in fact used in several countries to treat an overactive thyroid because it was so good at reducing thyroid function. With so many people suffering from problems of hypothyroid, many being undiagnosed, one can wonder how much of the problem can be related to tea and fluoridated water consumption. Fluoride's affect on the thyroid go way beyond blocking iodine, and are far too numerous to account for here. If dental fluorosis is present, hypothyroid is a given. Yikes! This is serious stuff!!
Dean Burk, who was Chief Chemist at the National Cancer Institute for several decades, said that "no chemical causes as much cancer, and faster, than fluorides", and fluoride is particularly problematic in uterine and bone cancers. Fluoride also tends to soften bones and make them brittle, playing a role in osteoporosis. Dental fluorosis or a mottling of the teeth is the first obvious sign of fluoride poisoning, and if there is dental fluorosis, there are hypothyroid problems, and probably skeletal fluorosis as well. Tea also frequently contains aluminum, and fluoride and aluminum together are even more problematic, creating renal and neurological problems, including possibly Alzheimers (aluminum fluoride which turns into aluminum oxide).
Chinese teas seem to have more fluoride in them than Indian, oolong and Ceylon teas, decaf teas have much higher levels of fluoride than caffeinated teas, and instant teas are full of fluoride too. Black teas have more fluoride than green, and longer brewing times increase the fluoride content. The higher the grade of tea, the less the fluoride, so in other words the expensive stuff really is better. In fact one study suggested that measuring fluoride content would be a good way to evaluate the quality of the tea. But even high quality tea has a fair bit of fluoride in it, so what are tea lovers to do?? Body Ecology makes black and green tea extracts that are fluoride and caffeine free. I guess that's where I'll be getting my tea from now on ... If you want more detailed information on this topic, I highly recommend this article by Andreas Schulds on Dr. Mercola's website. The book The Fluoride Deception by Christopher Bryson is also a good read.
I want to thank Sue Bond, who helped me considerably with the research for this post.
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Copyright 2008 Vreni Gurd
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