In a recent article from Nature Communications published on April 28, 2015, Dr. Stephen J. D. O’keefe and his colleagues conducted an interesting study looking at how diet affects mucosal biomarkers of colon cancer risk. They performed 2-week food exchanges in which African-Americans were fed a traditional African diet of high fiber and low fat and Africans were fed western style diet (high fat and low fiber). Colonoscopies were done and biopsies showed less inflammation of the colon and increased production of butyrate, a fatty acid that is thought to protect from colon cancer, in those who ate the traditional African style diet compared to western. Although no direct correlation of diet and colon cancer risk is stated by the authors, the results suggest that diet can have a profound and rapid effect on mucosa which may affect development of colon cancer. Check out the NY Times article below as well as the abstract and original article from Nature Communications and thanks to Dr. Bedimo for the reference!
African Diet May Lead Away from Colon Cancer (NY Times)
Fat, fibre, and cancer risk in African Americans and rural Africans (Nature Communications)
Rates of colon cancer are much higher in African Americans (65:100,000) than in rural South Africans (5:100,000). The higher rates are associated with higher animal protein and fat, and lower fibre consumption, higher colonic secondary bile acids, lower colonic short-chain fatty acid quantities and higher mucosal proliferative biomarkers of cancer risk in otherwise healthy middle-aged volunteers. Here we investigate further the role of fat and fibre in this association. We performed 2-week food exchanges in subjects from the same populations, where African Americans were fed a high-fibre, low-fat African-style diet and rural Africans a high-fat, low-fibre western-style diet, under close supervision. In comparison with their usual diets, the food changes resulted in remarkable reciprocal changes in mucosal biomarkers of cancer risk and in aspects of the microbiota and metabolome known to affect cancer risk, best illustrated by increased saccharolytic fermentation and butyrogenesis, and suppressed secondary bile acid synthesis in the African Americans.