Can Green Tea Protect Against Prostate Cancer?November 2005
By Coulson K. Duerksen
Green Tea and Cancer Prevention
Numerous animal and human cell studies suggest that green tea catechins may act as powerful inhibitors of cancer,17,18 particularly colon, rectal, and prostate cancers,19,20 as well as cancers of the lung, stomach, and kidney.21 Green tea catechins appear to be effective chemopreventive agents against a variety of carcinogens.
In addition to laboratory studies, population studies tracking the health of large groups of people who drink tea in abundance demonstrate the cancer-preventive benefits of green tea. Population studies have found reduced cancer rates in Asian countries where green tea is a dietary staple.22,23 In one Asian study, tea drinkers were about half as likely to develop stomach or esophageal cancer as men who drank little tea, even after adjusting for smoking and other health and dietary factors24 Japanese men, who commonly drink four to six cups of green tea daily, also have significantly lower rates of cancer incidence and mortality than Westerners.18,25
It has long been noted that the lung cancer rate in Japan is one of the lowest in the world, despite that nation’s high rate of smoking. Data from a case-controlled study conducted in Okinawa, Japan, from 1988 to 1991 showed that the greater the intake of Okinawa tea (a partially fermented tea), the smaller the risk of squamous cell lung cancer, particularly in women.26 These findings suggest that tea consumption has a protective effect against lung cancer in humans.
Another interesting fact relating to green tea consumption is that the cancer mortality rate in Shizuoka Prefecture, located in central Japan, is much lower than the Japanese average. As it turns out, green tea intake is even more habitual in the Shizuoka Prefecture than in other areas of Japan.27
FDA regulators believe the evidence that green tea prevents cancer is insufficient to merit a limited health claim, and that, based on the “limited” research available, green tea is highly unlikely to reduce the risk of prostate or any other type of cancer.
Given the limited information available concerning the biological processes that lead to the development of prostate cancer, it is wise to examine all possible prevention strategies. While a larger, confirmatory study is needed, the Bettuzzi study shows that green tea catechins may be an excellent prophylactic agent against prostate cancer in men at high risk for the disease.4
Most modern medicines used to treat cancer have serious side effects, high costs, and other associated risks. Green tea, on the other hand, is safe and widely available as a beverage and a nutritional supplement. Furthermore, growing scientific evidence suggests that green tea is effective in preventing many diseases associated with aging, including prostate and other cancers.
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