In "Gulp: Adventures on the Alimentary Canal," author Mary Roach discusses research findings that indicate a link between bowel health and rectal cancer risk in men. Specifically, frequent bowel movements have been found to correlate with a higher risk of developing rectal cancer, while constipation appears to be associated with a lower risk. This information aligns with long-standing discussions in the medical community about the role of diet and fiber in digestive health.

Mike Jones reflects on the ongoing skepticism among medical professionals regarding the importance of fiber, as proposed by researcher Denis Burkitt. Despite evidence supporting the benefits of dietary fiber, the medical community has not universally embraced these findings, which reveals a complex relationship between bowel habits and cancer risk. The insights presented in Roach's book highlight the need for continued research in this area.