Colon Cancer Risk Reduced With Added Fiber From Rural African Diet, Study Finds

There are numerous factors that play a role in cancer risk. Yet could our diet increase or decrease our risk of colon cancer?

New research published in the journal Nature Communications looks at how the respective risks of colon cancer are oftentimes reflected by alterations from our gut bacteria.

Researchers at the University of Pittsburgh School of Medicine looked at Africans and African-Americans who changed their diets for just a two-week period to see how it affected their risk level. They studied the diets of 20 African Americans from Pittsburgh and 20 rural Africans in KwaZulu-Natal in their homes. African Americans were more likely to eat higher amounts of fat and animal protein than rural counterparts, according to The Guardian. 

During the study, meals provided by a set of health staff included ingredients and cooking techniques typical of the other group. Researchers then looked at fecal and colon content samples that had been collected from a colonoscopy before and right after the study.

"The African-American diet, which contains more animal protein and fat, and less soluble fiber than the African diet, is thought to increase colon cancer risk," Principal investigator Stephen O'Keefe, M.D., professor of medicine, Division of Gastroenterology, Hepatology and Nutrition, Pitt School of Medicine, said via Medical Xpress. "Other studies with Japanese migrants to Hawaii have shown that it takes only one generation of Westernization to change their low incidence of colon cancer to the high rates observed in native Hawaiians. In this project, we examined the impact of a brief diet change on the colon in a controlled setting where we didn't have to worry about the influence of smoking and other environmental factors on cancer risk."

Researchers found that African-American participants experienced an increase in butyrate production, which is believed to be important in anti-cancer pathways. Furthermore, researchers found that increasing fiber in the diet from approximately 10 grams to more than 50 grams for African-Americans in the diet swap helped to reduce the risk of colon cancer, overall.

"These findings are really very good news," he concluded. "In just two weeks, a change in diet from a Westernized composition to a traditional African high-fiber, low-fat diet reduced these biomarkers of cancer risk, indicating that it is likely never too late to modify the risk of colon cancer."