By swapping diets, rural South Africans and African Americans altered their gut bacteria and risk of developing colon cancer, researchers from the University of Pittsburgh and elsewhere report in Nature Communications.
For two weeks, 20 South Africans ate high-fat, low-fiber Western-style diet, while 20 African Americans in Pittsburgh ate a high-fiber, low-fat African-style diet.
"We made them fried chicken, burgers, and fries," study author Stephen O'Keefe, from Pittsburgh says of the rural South Africans in the New York Times. "They loved it."
After two weeks on the African-style diet, not only did the African Americans in Pittsburgh have decreased inflammation in their colons, they also had changes to their gut microbiomes and metabolomes. In particular, the researchers noted a rise in butyrogenesis. These changes, the researchers say, likely also affect the participants' risk of developing colon cancer, as chronic inflammation is a disease risk factor.
The South African participants, meanwhile, showed the opposite effects. This, the researchers say, may portend what is to come as rural African communities become westernized and their diets change.
"We're trying to find out what aspects of their diet should be maintained," O'Keefe adds.