The next time you swallow an aspirin to calm a headache, think about it: this simple gesture could help to silently slow down the development of certain tumors. Nick James, a British furniture maker, is convinced of this. After his mother, brother and several family members developed bowel cancer, he decided to pursue genetic testing. Result: the forty-year-old carries a gene that causes Lynch syndrome, a disease that skyrockets the risk of colorectal cancer. Depending on the mutations, between 10 and 80% of people affected develop this type of cancer.
Faced with this risk, Nick James agreed to participate in a large-scale clinical trial, testing the effect of taking daily aspirin on tumor development. “He has been taking aspirin for ten years now and we have detected no signs of cancer to date», Underlines John Burn, professor of clinical genetics at the University of Newcastle, who led the study.
Aspirin, miracle cure for the disease of the century? The idea may seem excessive. However, the properties of aspirin have fascinated researchers for a long time, as outlined in a BBC article. As early as 1763, the English reverend Edward Stone described the febrifuge properties of salicin, a chemical substance contained in willow bark. A century later, scientists managed to synthesize a less aggressive version: acetylsalicylic acid, which was then marketed on a large scale by the pharmaceutical giant Bayer.
Since the 1970s, pharmacologists have analyzed the potential anti-cancer properties of the precious pill. Animal experiments have shown that aspirin may slow the spread of tumors. But translating these results to humans remained a challenge.
Renewed interest among researchers
A turning point came in 2010, when Peter Rothwell, professor of clinical neurology at the University of Oxford, delved into decades of scientific data surrounding aspirin. Its findings suggested that the drug could reduce both the incidence and spread of cancers. Enough to massively revive scientific interest.
In this context, John Burn became interested in patients with Lynch syndrome. For ten years, he followed nearly 900 patients. The results published in 2020 are clear: a daily dose of 600 mg of aspirin halves the risk of colorectal cancer.
His team has since conducted a second study, which is still being evaluated. Early results suggest that a much lower dose (75 to 100 mg) could be just as effective, or even better. “In people who took aspirin for two years, the development of colon cancer was reduced by half»he reports. Another advantage: low doses are better tolerated.
Results that influence health policies
The findings of this research have influenced health policies across the Channel, where doctors now recommend that people with Lynch syndrome begin treatment from the age of 20.
Other studies reinforce these observations. A clinical trial carried out on nearly 3,000 people with colorectal cancer showed that taking 160 mg of aspirin daily three months after surgery halved the risk of recurrence. Since January 2026, in Sweden, patients with bowel cancer have been tested for certain mutations to determine whether they can benefit from the treatment.
The effect of aspirin on cancer risks remains partly mysterious. “This medicine works both inside and outside the cell»explains Anna Martling, professor of surgery at the Karolinska Institute in Sweden. Aspirin notably inhibits an enzyme called Cox-2, involved in the production of prostaglandins – molecules that promote uncontrolled cell proliferation.
More recently, research carried out by Rahul Roychoudhuri, professor of cancer immunology at the University of Cambridge, puts forward another hypothesis. Thromboxane A2, a molecule linked to blood clotting, could activate a mechanism preventing T lymphocytes from identifying cancer cells. By blocking this process, aspirin would make these cells more visible to the immune system. An encouraging result, but still limited to experiments on mice.
However, scientists urge caution. The questions of who should take aspirin, in what dosage and how often remain open. John Burn is optimistic: “Our research shows that if everyone in their 50s took a low dose of aspirin for ten years, overall national mortality could decrease by 4%.“. An optimistic projection, which still needs to be confirmed on a large scale.
