A new study has found that long-distance runners may be at a higher risk of developing colon cancer, particularly among those under 50 years old. Researchers from DC-based scientists observed that participants who regularly ran marathons had a higher incidence of precancerous tumors and advanced adenomas compared to the general population.
The study involved 100 patients aged 35-50 years who were ultramarathon runners. Out of these, 41% had at least one benign tumor in their colon, while 15% had more advanced growths. Notably, over half of those with advanced adenomas reported experiencing rectal bleeding, a warning sign of cancer.
Medical oncologist Dr. Timothy Cannon led the research and warned that any runners experiencing similar symptoms should get tested for colon cancer regardless of age. The study’s findings suggest that prolonged periods of running may cause blood to be diverted away from the colon, potentially leading to cell death and mutations.
The link between marathon running and colon cancer has raised concerns among health experts, particularly in light of a surge in early-onset colon cancer diagnoses among young adults. While more research is needed to understand the relationship between distance running and other lifestyle factors, Dr. Cannon emphasized the importance of awareness and regular screenings for colon cancer.
Source: https://www.dailymail.co.uk/health/article-14768309/colon-cancer-running-asco-2025.html