In research involving 50,000 men over 20 years, scientists led by Kathryn Wilson at Harvard’s Channing Laboratory found that the 5 percent of men who drank 6 or more cups a day had a 60 percent lower risk of developing the advanced form of the disease than those who didn’t consume any. The risk was about 20 percent lower for the men who drank 1 to 3 cups a day, and 25 percent lower for those consuming 4 or 5 cups.
The study is the first to associate coffee with prostate cancer, contradicting previous research that’s found no link. The difference may be because Wilson and colleagues looked for the first time at the link between coffee and different stages of the disease, instead of grouping them all together. More research is needed to confirm the findings, she said.
“People shouldn’t start changing their coffee consumption based on one study,” Wilson said in a phone interview on Dec. 5. “It could be chance, and we really need to see whether it pans out in other studies.”
Prostate cancer struck almost 200,000 men in the U.S. this year and killed more than 27,000, making it the second-deadliest malignancy among American men after lung cancer, according to the American Cancer Society. About 54 percent of U.S. adults drink coffee, according to the New York-based National Coffee Association.
The researchers aren’t sure which of the many components of coffee is responsible for the effect, though it probably isn’t caffeine because the same association was seen for decaffeinated coffee, Wilson said. The link wasn’t seen in patients with an earlier stage of prostate cancer, she said.
Coffee lowers the risk of Type 2 diabetes by increasing the body’s ability to use insulin to convert blood sugar to energy, previous research has shown.
Higher insulin levels have also been associated with an increased risk of prostate cancer, suggesting the hormone may be the link between coffee and the disease, Wilson said.
The data were presented at an American Association for Cancer Research conference in Houston.
To contact the reporter on this story: Simeon Bennett in Singapore at email@example.com
Last Updated: December 8, 2009 01:21 EST