Study Furthers Evidence of Black Tea's Cancer Reducing Abilities
A number of previous studies have linked green tea reducing the risk of cancer. Now a new study has found that black tea may provide similar benefits.
The study was conducted by researchers at Annamalai University in India and published in the September 2010 issue of the journal Food and Chemical Toxicology.
For the study, the researchers ran lab tests that involved exposing cancer induced cells to black tea polyphenols, the powerful antioxidants found in tea. The polyphenols specific to black tea are known as polyphenon-B.
The researchers found that the development of cancer was inhibited when the cells were exposed to the black tea polyphenols. They also found that uncontrolled cell growth, which plays an important role in the development of cancer, was inhibited in a dose dependent manner.
In addition, the researchers gave rats the black tea polyphenol and observed a reduction in tumor incidence.
The most in depth scientific research on tea to date has been conducted on green tea, which has been shown to improve heart health, digestion and decrease the risk of neurogenerative disease.
Green tea is only one of the 3 most popular types of tea, however, and recent studies are finding similar benefits of the black tea and white tea. They are all from the same plant (Camellia sinensis) and vary only in the amount of oxidation they are exposed to during fermentation, which directly affects polyphenol levels.
White tea is purported to contain the greatest percentage of polyphenols because it is not fermented or oxidized. Green tea is slightly oxidized and contains the second highest level of polyphenols. Black tea, which is green tea that has been oxidized by fermentation, contains the least amount of polyphenols.