Bloomberg News reports that a study in the medical journal Gut found that "people who take even a very low dose of aspirin every day for five years can cut the risk of developing colon cancer by almost a third." According to researchers, "as little as 75 milligrams of aspirin a day...lowered the risk of colon cancer by 22 percent after just a year." While it was already know that aspirin can protect the colon, the "study showed for the first time that a low dose of aspirin is sufficient to ward off cancer, and that the drug needs to be taken for at least five years to get the full benefit."
According to MedPage Today "Aspirin has not as yet been recommended for primary chemoprevention of colorectal cancer...because of unanswered questions on dose, duration, and effects on survival." WebMD the UK's Press Association and the UK's Daily Mail also covered this study.