Even people not at high risk of the disease could benefit from the painkiller, with the positive effects mounting up over time.
Researchers writing in the journal Gut studied almost 2,800 people with bowel cancer and nearly 3,000 healthy people.
Their intake of non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin or ibuprofen, was taken into account.
Overall, 16% of people with bowel cancer were taking a low dose of aspirin compared with 18% of those in the healthy group.
People also responded to questions about their diet and lifestyle, which are known to have a big impact on the risk of bowel cancer.
The results showed that those who took a daily low dose of 75mg of aspirin had a lower chance of developing the disease.
Taking 75mg of aspirin every day for between one and three years led to a 19% reduction in risk.
For people taking the drug daily for three to five years, there was a 24% reduced risk, rising to 31% for those taking the drug for five to 10 years.
Doubling the dose did not lead to any extra benefit, suggesting “the lowest dose of aspirin is effective”, and benefits were apparent even at one year, the experts said.
The Press Association