According to a University of Pittsburgh researcher, the typical Western diet – rich in meat and fats and low in complex carbohydrates -increases the risk of colon cancer.
Professor Stephen O’Keefe from the University of Pittsburgh presented his conclusions to the Society for General Microbiology meeting in Harrogate, UK, on March 31.
They are based on growing evidence that the composition of the diet influences the diversity of intestinal microbes, supporting the link between diet, colonic disease and colon cancer, the second leading cause of cancer-related deaths in adults in the West.
In particular, those whose diet is rich in complex carbohydrates have significant populations of bacteria in their gut called Firmicutes which use undigested residues to synthesize short-chain fatty acids and vitamins such as folate and biotin that maintain colonic health.
By contrast, meat digestion produces sulphur, which decreases the activity of ‘good’ bacteria and increases the production of hydrogen sulphide and other possible carcinogens.
"Our investigations to date have focused on a small number of bacterial species and have therefore revealed but the tip of the iceberg," says Professor O’Keefe, adding that the colon harbors more than 800 bacterial species and 7,000 different strains.
"The characterization of their properties and metabolism can be expected to provide the key to colonic health and disease," he adds.
The study also demonstrates how simple dietary changes may prevent a serious illness that requires medical intervention.