A new U.S. study has found more evidence for the health-giving properties of coffee, finding that more than 2.5 cups of coffee a day can significantly decrease your risk of colorectal cancer.

To carry out their study, researchers at the University of Southern California looked at a group of 5,145 participants with colorectal cancer, and a further 4,097 participants without colorectal cancer as a control group. Those that had colorectal cancer had all been diagnosed within the last 6 months.

Data on coffee consumption was collected by interview and food frequency questionnaires, which participants completed to report on how much coffee they drank, whether it was boiled (espresso), instant, decaffeinated or filtered.

After they took into consideration other cancer risk factors, the team found that even just one to two cups of coffee a day reduced the risk of developing colorectal cancer by 26 per cent. And when coffee consumption was increased to more than 2.5 cups of coffee a day, the risk decreased by up to 50 per cent.

And although the levels of coffee's beneficial compounds vary depending on the bean, roast and how it is brewed, the results showed that it also didn't matter how the coffee was taken, with espresso, filter, and even instant coffee all having a beneficial effect.

And although caffeine can act as an antioxidant in the body, preventing the growth of potential colon cancer cells, the results were also seen whether coffee was taken decaf or fully caffeinated.

"We were somewhat surprised to see that caffeine did not seem to matter," commented senior author of the study Stephen Gruber, "This indicates that caffeine alone is not responsible for coffee's protective properties."

And although Gruber commented that "We need additional research before advocating for coffee consumption as a preventive measure," he also added, "That being said, there are few health risks to coffee consumption, I would encourage coffee lovers to revel in the strong possibility that their daily mug may lower their risk of colorectal cancer."