Fighting prostate cancer is "E"asy
Vitamin E can protect men from prostate cancer, according to researchers. Men with high levels of the alpha tocopherol form of vitamin E were 53 per cent less likely to develop prostate cancer. The researchers stressed it was better to take vitamin E from fresh food than supplements. The US National Cancer Institute study was presented at the American Association of Cancer Research annual meeting in Orlando.
Scientists looked at 100 men who had prostate cancer and 200 who did not and compared amounts of vitamin E in the bloodstream before and after taking a supplement. Stephanie Weinstein at the institute said: "We found that the men who had the higher serum levels of vitamin E had a lower chance of getting prostate cancer." The researchers then looked at the two main forms of vitamin E - alpha tocopherol and gamma tocopherol. Men with the highest natural levels of alpha tocopherol were 53 percent less likely to later develop prostate cancer. Men with the highest levels of gamma tocopherol, which only represents about 20 percent of the vitamin E in blood, had a 39 percent lower chance. In other research, in the first known study of the absorption and anti-tumor effects of green and black tea polyphenols in human tissue, researchers at the University of California at Los Angeles were able to detect tea polyphenols in prostate tissue after a very limited consumption of tea. More importantly, the scientists found that prostate cancer cells grew more slowly when placed in a medium containing blood serum of men who had consumed either green or black tea for five days compared to serum collected before the men began their tea-drinking regimen. Serum from men who drank comparable amounts of diet or regular soda showed no such slowing in cancer cell proliferation.
Recent animal and epidemiological studies have suggested tea may have anti-tumor effects against carcinoma of the prostate, and many of the polyphenolic components of tea have been found in the prostate and many other tissues in rats and mice after chronic consumption of green tea polyphenols in drinking water.
Five days before they were to undergo radical prostatectomy, 20 men with prostate cancer were randomly assigned to consume daily either five cups of green tea, five cups of black tea, or diet or regular soda containing no tea polyphenols. Their blood serum was then collected and added to prostate tissue samples from a commercially available prostate cancer cell line called LNCaP. Analysis of the prostate tissue showed a large variation in tea polyphenol content between study participants. Tea polyphenols were found in six out of eight participants drinking green tea, seven out of seven drinking black tea, and two out of five drinking soda. The fact that two of the control participants showed polyphenols in the prostate sample might be because they were eating chocolate regularly or drinking tea before entering the study. Chocolate does contain the polyphenols epicatechin and epicatechingallate, and the turnover rate of these polyphenols - how long they might remain in tissue - is not known. They are water-soluble and are all excreted after eight hours. The maximum concentration in plasma is after two to three hours. When the scientists measured the proliferation of prostate cancer cells, there was a significant decrease in how fast new cancer cells appeared for the men who had consumed either green or black tea. That was true even when no tea components could be detected in the serum, indicating, says Dr. Henning, that the inhibition of cell proliferation was caused by other compounds altered through tea consumption. Paul Ellis
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