When black Americans switched their diet from a typical Western one to that of South Africans, their risk for colon cancer dropped within weeks, in a study from the University of Pittsburgh. In this study, 20 black American volunteers and 20 adults from rural South Africa swapped diets for two weeks. Colonoscopies were conducted at the beginning and end of the study. At the start, almost 50% of the American group had polyps, or abnormal growths, in the lining of the colon. A condition that can progress eventually to cancer. None of the South Africans had polyps. After two weeks of eating the African diet, the American volunteers showed dramatic reductions in colon inflammation and other signs associated with colon cancer risk. In contrast, the Africans who had made the switch to a diet high in fat and protein and low in fiber showed increased risk factors for colon cancer. The researchers speculate that part of the benefits noted in the American group resulted from changes in the gut microbiome, which mediate the link between diet and colon cancer.
Colon cancer patients have the best odds of survival if they had already been practicing healthy lifestyle habits, such as eating a healthy diet, exercising daily, and maintaining a fit weight, prior to diagnosis, state researchers at Imperial College London.
O’Keefe S, Li J, Lahti L, et al: Fat, fibre and cancer risk in African Americans and rural Africans. Nature Communications 2015; April 28;6:6342.
Romaguera D, Ward H, Wark P, et al: Pre-diagnostic concordance with the WCRF/AICR guidelines and survival in European colorectal cancer patients. BMC Medicine 2015;13:107.