The second most common form of cancer in American men, prostate cancer is more than just a little bit scary. Each year in the U.S. more than 220,000 men receive the unwelcome news that they've developed prostate cancer, and 31,000 men die of the disease. Yet in Asian countries, the rates of prostate cancer are surprisingly low. Why are they so lucky? Many researchers think it may have to do with their tea consumption.
At least two studies of large populations have shown that men who regularly consume tea (black or green) have a lower incidence of prostate cancer.1,2 Researchers have discovered that risk of developing this killer disease decreases as the frequency, duration and quantity of green tea consumption increases.3 And a study of a group of men with pre-cancerous prostate "wounds" (lesions) found that those who received daily doses of green tea catechins were 90 percent less likely to develop full-blown prostate cancer than those who didn't receive catechins.4
How do the researchers think it works? Well, for starters, once the green tea is ingested, its catechins make their way through the bloodstream and settle into the prostate tissue.5 From there, they may help fight prostate cancer in a variety of ways:
- According to the results of "test tube" studies, the catechin EGCg slows the growth of human prostate cancer cells and promotes cancer cell “suicide.”6
- Animal studies have shown that green tea catechins reduce the activity of an enzyme called ornithine decarboxylase (ODC), which may play a part in the start-up of prostate cancer.7
- EGCg inhibits an enzyme called COX-2, which is implicated in prostate cancer and found in large quantities in prostate cancer tissue.8
- COX-2 inhibitors, like celecoxib (brand name Celebrex) inhibits the growth of prostate cancer in animals. But a 2007 study published in Clinical Cancer Research found that EGCg fights prostate cancer almost as effectively as celecoxib. And when the two are combined, the results are much better than either alone.9
While no one is suggesting that drinking green tea is a solution to the prostate cancer problem, it does look like it may be able to help. So see your doctor for regular checkups, eat healthfully, get plenty of exercise and keep drinking your green tea!
Decreased Risk of Prostate Cancer With Increased Consumption of Green Tea
Participants: 404 people: 130 who had prostate cancer and 274 hospital inpatients who did not have prostate cancer or other malignant diseases
Where: Hangzhou, China
Type of study: Case-control
Study Methods: The green tea-drinking habits of all subjects were collected in face-to-face interviews, noting the duration, quantity and frequency of usual green tea consumption, and the number of new batches brewed per day.
What happened: The risk of prostate cancer decreased with the increasing frequency, duration and quantity of green tea consumption. Compared to the non-green tea drinkers, the prostate cancer risk decreased 72% for the tea drinkers, 73% for those drinking more than 3 cups/day, 88% for those who had been drinking green tea for more than 40 years, and 91% for those consuming more than 1.5 kg green tea leaves per year (an average of about 1 1/2 cups of tea per day).
Researchers' conclusion: “The dose response relationships were also significant, suggesting that green tea is protective against prostate cancer.”
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