Study Links E. coli Toxin to Surge in Young Bowel Cancer Cases Worldwide

A series of new studies have identified colibactin, a DNA-damaging toxin produced by certain strains of E. coli in the gut, as a potential driver of the global rise in early-onset colorectal (bowel) cancer among people under 50. Researchers found that specific genetic mutations linked to colibactin were over three times more common in tumors from younger patients compared to older adults, particularly in countries experiencing sharp increases in early-onset cases. These mutations appear to occur when children are exposed to colibactin within their first decade of life, leaving a lasting genetic fingerprint that may accelerate the development of colorectal cancer. Other factors such as poor diet, obesity, and physical inactivity have previously been implicated, but this evidence suggests early-life microbial exposure plays a significant role. Experts say the findings could reshape understanding of cancer risk, highlighting the importance of early-life influences on long-term health. The research underscores the need for further investigation into how early childhood exposures affect cancer risk later in life.