Green and black tea – healthy or not?
Green and black tea are full of anti-oxidants and polyphenols which are good for us, but they also contain very high amounts of fluoride, which is highly toxic to the body.
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 as much as 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.
If you want more detailed information on this topic, I recommend the book by Christopher Bryson is also a good read.
Non-organic teas are frequently riddled with pesticides, and do read labels to check for soy lecithin or corn starch, which are most certainly genetically modified. Many herbal teas contain colourings and flavourings also, which are not healthy.
Furthermore, I strongly suggest buying organic or non-GMO-certified LOOSE tea instead of tea in bags, as the bags can be a problem too. Paper tea-bags frequently contain the chemical “epichlorohydrin”, which is a carcinogen, and plastic tea-bags can leach endocrine disrupting phthalates.
I want to thank Sue Bond, who helped me considerably with the research for this post.
Related tips
Fluoridated water – boon or bane?
Choosing a water filtration system
Our toxic body burden
Thyroid function and dysfunction
The three keys to preventing osteoporosis
Malinowska E et al. Assessment of fluoride concentration and daily intake by human from tea and herbal infusions. Food Chem Toxicol. 2008 Mar; 46(3): 1055-61. Epub 2007 Nov 5.
Cao J et al. Fluoride levels in various black tea commodities: measurement and safety evaluation. Food Chem Toxicol. 2006 Jul;44(7):1131-7. Epub 2006 Feb 28.
Lu Y et al. Fluoride content in tea and its relationship with tea quality. J. Agric Food Chem. 2004 July 14; 52(14): 4472-6.
Whyte MP et al. Skeletal Fluorosis from instant tea.J Bone Miner Res.2008 Jan 7 [Epub ahead of print
Hayem G, Ballard M, Palazzo E, Somogyi N, Roux F, Meyer O. Insufficiency bone fractures due to fluorosis in heavy tea drinkers. Annals of the Rheumatic Diseases 63(Suppl 1): 488, 2004
Shu WS et al. Fluoride and aluminium concentrations of tea plants and tea products from Sichuan Province, PR China. Chemosphere 2003 Sep; 52(9): 1475-82.
Cao J et al. Brick tea fluoride as a main source of adult fluorosis. Food Chem Toxicol. 2003 Apr;41(4):535-42.
Anuradha CD, Kanno S, Hirano S.
Fluoride induces apoptosis by caspase-3 activation in human leukemia HL-60 cells. Arch Toxicol 2000 Jul;74(4-5):226-30
NTEU – “Why EPA’s Headquarters Union of Scientists Opposes Fluoridation” Prepared on behalf of the National Treasury Employees Union Chapter 280 by Chapter Senior Vice-President J. William Hirzy, Ph.D.
Zhao, L.B., Liang, G.H., Zhang, D.N., and Wu, X.R. – “Effect of high fluoride water supply on children’s intelligence” Fluoride 29; 190-192 1996
Chan J.T.; Koh, S.H. -“Fluoride content in caffeinated, decaffeinated and herbal teas” Caries Res 30(1):88-92 (1996)
Tohyama, E. et al. “Relationship between fluoride concentration in drinking water mortality rate from uterine cancer in Okinawa prefecture” Japan. J Epidemiol (CL8); 6 (4): 184-91 1996
Gulati P et al. "Studies on the leaching of fluoride in tea infusions” Sci Total Environ. 138(1-3):213-21 1993
Opinya GN et al. “Intake of fluoride and excretion in mothers’ milk in a high fluoride (9ppm) area in Kenya” Eur J Clin Nutr 45(1):37-41 (1991)
Wei, S.H.; Hattab, F.N., Mellberg, J.R. – “Concentration of fluoride and selected other elements in teas” Nutrition 5(4):237-40 (1989)
Sergio Gomez S, Weber A, Torres C – “Fluoride content of tea and amount ingested by children” Odontol Chil 37(2):251-5 1989
C.A. Jones, et al.Sodium Fluoride Promotes Morphological Transformation of Syrian Hamster Embryo Cells, Carcinogenesis Volume 9, pp.2279-2284 (1988)
Copyright 2008 Vreni Gurd