In populations with high rates of colorectal, prostate, and breast cancer, cancer risk can be moderately reduced with a daily dose of adult-strength aspirin (at least 325mg/day) if taken for at least five years.
Eric Jacobs, Ph.D., of the American Cancer Society, together with colleagues looked for associations between long-term daily aspirin use (at least 325mg/day) and cancer incidence in a group of nearly 70,000 men and 76,000 women and during the 12-year follow-up found the following:

daily use of adult-strength aspirin for at least five years was associated with an approximately 15 percent relative reduction in overall cancer risk …read more