Not just four cups of coffee, as new research suggested this week, just a daily cup-full of the cranberry super fruit can also combat colon cancer.

To reach this conclusion, researchers fed cranberry extracts to mice with colon cancer and found that their tumours diminished in size and number.

Identifying the therapeutic molecules in the fruit could lead to a better understanding of its anti-cancer potential, they said.

"Colon cancer may offer a particularly good target for a dietary treatment. Cranberry extracts may also afford protection toward other cancers," said Catherine Neto from University of Massachusetts, Dartmouth.

Neto and colleagues found that chemicals derived from cranberry extracts could selectively kill off colon tumour cells in laboratory dishes.

This is approximately equivalent to a cup a day of cranberries if you were a human instead of a mouse,"

"We have identified several compounds in cranberry extracts over the years that seemed promising, but we've always wanted to look at what happens with the compounds in an animal model of cancer," Neto noted.

"Cranberry constituents and metabolites should be bioavailable to the colon as digestion proceeds," she added.

However, she is not sure someone could get the same benefits from juice which lacks some of the components in the skin of the cranberry.

Neto is now looking deeper into the cranberry to see if she can isolate individual components responsible for its anti-cancer properties.

The team were set to describe their approach at the national meeting and exposition of the American Chemical Society (ACS) in Boston this week.