Men interested in reducing their risk of prostate cancer might consider heading over to the nearest café — or buying a new coffee maker. Drinking several cups of coffee every day seems to be linked to a lower risk of developing prostate cancer, a study finds. And the risk goes down 1 percent for every added cup.
Prostate cancer is the the sixth leading cause of cancer death and second most common cancer in men. It is seen most often in the developed world, where nearly three out of four cases occur. New cases of the disease have risen sharply Japan, Singapore and China.
Coffee drinking has been linked to a lower relative risk of liver, colon and breast cancers and a longer life in general, but the evidence surrounding its value in preventing prostate cancer has been inconclusive. So Chinese researchers pooled the findings from 16 studies that tracked coffee consumption in North America, Europe and Japan.
It's not just about caffeine: Coffee contains hundreds of other biologically active ingredients, any of which could be responsible for its health benefits.
Those who were in the high-consumption group had a 9 percent reduction in cancer risk, compared with men who had no coffee or less than two cups a day. For each cup a man drank beyond two a day, his risk of developing prostate cancer went down 1 percent.
Both local prostate cancer, cancer confined to the prostate itself and advanced prostate cancer were tracked in the studies included in the analysis. Compared with men with the lowest coffee intake, men who consumed the most coffee had a 7 percent lower risk of localized prostate cancer. Their risk of having advanced and fatal prostate cancer was reduced by 12 and 16 percent respectively.
There are a number of possible explanations for why coffee may help guard against prostate cancer, the researchers say. It's not just about caffeine: Coffee contains hundreds of other biologically active ingredients, any of which could be responsible for its health benefits. Coffee also has anti-inflammatory and antioxidant properties. It affects sex hormone levels and improves glucose metabolism. Any or all of these influences could impact the initiation, development and progression of prostate cancer.
The type of coffee and brewing methods varied among the studies used in the analysis, and the data relied on men’s memories of their coffee consumption and so may not have been accurate, both reasons to view the results with caution, according to the China Medical University researchers. In addition, this was an analysis of many studies involving different designs and methods and with various unmeasured or uncontrolled factors, all of which could have skewed the results.
The study is published in BMJ Open.