A study led by Harvard University and published in Cell Host & Microbe found that more than a decade after the removal of a precancerous mass known as an adenoma from the colon, changes in the gut microbiome and certain metabolites persist, potentially contributing to an elevated risk of colorectal cancer (CRC). The study also found that a poor diet and limited physical activity are more closely associated with the abundance of these CRC-related gut microbes in people with a history of adenoma compared to adenoma-free individuals, suggesting that lifestyle choices play an important role in the gut microbiome of this high-risk group.

CRC is the second leading cause of cancer-related deaths globally, and the removal of adenomas is one of the most effective prevention procedures. However, people that have undergone this measure still face an elevated risk of developing CRC. The study involved more than 700 participants—half with a history of adenoma and the other half without. Researchers observed that further research is needed to determine whether modifying the gut microbiome through diet and exercise reduces the risk of CRC.