Daily aspirin does not lower colorectal cancer risk, review finds

• Colorectal, or bowel, cancer is the third most common cancer worldwide, making up 10% of cancer diagnoses.
• It most commonly affects people over the age of 50, but cases in younger people are increasing.
• Studies have found that in people with a genetic risk, such as Lynch syndrome, daily aspirin can cut their risk of colorectal cancer.
• However, a new review has found that, for the general population, daily aspirin appears to offer no protection against colorectal cancer, and may have other adverse effects.

Colorectal, or bowel, cancer is the third most common cancer worldwide. According to the World Health Organization (WHO), in 2022 alone there were 1.9 million new cases of colorectal cancer and it caused more than 900,000 deaths around the world.

Although most cases occur in people over the age of 50, in some countries incidence is rising in younger people. But the condition can be prevented by following a healthy lifestyle, and screening to detect early signs.

Some research has suggested that, in people with a genetic risk for colorectal cancer, a daily low dose of aspirin can reduce that risk.

Other studies have shown that it may help prevent recurrence in people who have had colorectal cancer.

But a new review of the evidence, carried out by researchers from West China Hospital of Sichuan University in China, and published in the Cochrane Database of Systematic Reviews, suggests that for people without genetic risk or prior colorectal cancer, there is no evidence that taking daily aspirin reduces colorectal cancer risk.

Lead author Bo Zhang, MD, of the Department of General Surgery, West China Hospital, Sichuan University in Chengdu, China, co-senior author of the review stated in a press release that:

“As scientists, we must follow the evidence where it leads. Our rigorous analysis of the highest-quality trials reveals that the ‘aspirin for cancer prevention’ story is more complex than a simple ‘yes or no.’ The current evidence does not support a blanket recommendation for aspirin use purely to prevent bowel cancer.”