Tea, particularly tea drinks made with lower quality older leaves, contain high levels of fluoride. Because of these high levels, research has found that individuals who drink large amounts of tea can develop skeletal fluorosis — a painful bone disease caused by excessive fluoride intake.

Since skeletal fluorosis is often misdiagnosed by doctors as arthritis, tea drinkers with skeletal fluorosis can suffer significant symptoms (e.g., joint pain, fragile bones) for years without being properly diagnosed and treated. As noted by a team of Chinese researchers who have carefully studied the impacts of tea intake on bone health, “it is certain that some heavy-tea drinkers suffering from fluorosis from tea-drinking might not be diagnosed.” According to these researchers:

“It is urgent that governmental and international agencies adopt safe standards of fluoride content in tea commodities.”

SOURCE: Yi J, Cao J. (2008). Tea and fluorosis. Journal of Fluorine Chemistry 129:1976-81.

The following studies highlight the high levels of fluoride found in common tea products. To read research linking tea intake to skeletal fluorosis, click here.

Excerpts from the Scientific Literature:

“It is urgent that governmental and international agencies adopt safe standards of fluoride content in tea commodities.”

SOURCE: Yi J, Cao J. (2008). Tea and fluorosis. Journal of Fluorine Chemistry 129:1976-81.

“Instant tea, one of the most popular drinks in the United States, may be a source of harmful levels of fluoride… The researchers found that some regular strength preparations contain as much as 6.5 parts per million (ppm) of fluoride, well over the 4 ppm maximum allowed in drinking water by the Environmental Protection Agency.”

SOURCE: ‘Potentially harmful fluoride levels found in some instant tea”, Washington University School of Medicine, January 25, 2005.

“Another important source of fluoride ingestion is tea…[T]he fluoride content of tea has been found to range from 0.1 to 4.2 ppm fluoride, with an average of about 3 ppm.”

SOURCE: Levy SM, Guha-Chowdhury N. (1999). Total fluoride intake and implications for dietary fluoride supplementation. Journal of Public Health Dentistry 59: 211-23.

“[M]ost of the iced teas studied contained considerable fluoride concentrations. If infants ingest larger amounts of them because of their sweet taste, there is a risk of uncontrolled overdosing as a result of additional fluoride intake from other sources at the same time. ”

SOURCE: Behrendt A, Oberste V, Wetzel WE. (2002). Fluoride concentration and pH of iced tea products. Caries Research 36(6): 405-410.

“The average fluoride concentration of infusions prepared from decaffeinated (green & black) tea in this study is 3.19 ppm and ranged from 1.01 to 5.20. This is unexpectedly higher than caffeinated tea and such a difference is statistically significant. If decaffeinated tea were prepared with optimally fluoridated water, the fluoride content would be increased by 1 ppm and would reach an average of 4.19 ppm.”

SOURCE: Chan JT, Koh SH. (1996). Fluoride content in caffeinated, decaffeinated and herbal teas. Caries Research 30:88-92.

FLUORIDE CONTENT IS HIGHER IN OLDER, LOWER QUALITY TEA:

“Older tea (lower grade), such as brick tea, contains higher amounts of fluoride than higher-grade teas.”

SOURCE: Hallanger Johnson JE, et al. (2007). Fluoride-related bone disease associated with habitual tea consumption. Mayo Clinic Proceedings 82(6):719-24.

“The tea plant is known as a fluorine accumulator. Fluoride (F) content in fresh leaves collected from 14 plantations in China was investigated. The F increased with maturity, and the F variation was remarkable in the tender shoots. Furthermore, significant negative relationships were observed between F content and the content of the quality parameters total polyphenols and amino acids. These substances are rich in young leaves and poor in mature ones. With regard to quality of tea products, the relationship with F content was studied using 12 brands of tea products in four categories: green tea, oolong tea, black tea, and jasmine tea collected from six provinces. The F level increased with the decline in quality and showed good correlation with the quality grades. The results suggest that the F content could be used as a quality indicator for tea evaluation.”

SOURCE: Lu Y, et al. (2004). Fluoride content in tea and its relationship with tea quality. J Agric Food Chem. 52(14):4472-6.

TABLES: PUBLISHED DATA ON FLUORIDE CONTENT IN TEA PRODUCTS

Brewed Black Teas Tea Number of Samples Tested Average Fluoride Content Traditional brew 97 3.37 ppm Microwave brew 36 3.22 ppm With caffeine 99 3.54 ppm With caffeine, traditional brew 63 3.73 ppm Decaffeinated 34 2.70 ppm SOURCE: USDA. (2005). The Fluoride Content of Brewed and Microwave Black Teas. Nutrient Data Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, US Department of Agriculture. Available online.