We all know that modern diets, based on fast food and heavily processed foods are unhealthy. We also know that rural populations often eat healthier, more natural foods. So what would happen if we swapped the two? A group of American researchers did just that: they had average Americans eat rural African diets, and had the Africans eat an American diet. The results were shocking.
"In just two weeks, a change in diet from a Westernised composition to a traditional African high-fibre, low-fat diet reduced these biomarkers of cancer risk, indicating that it is likely never too late to modify the risk of colon cancer," lead researcher Stephen O'Keefe from the University of Pittsburgh in the US told Sarah Berry at The Age.
To be honest, the results weren't completely unexpected, but it was surprising to see just how quickly the changes take place. The authors report in the journal Nature Communications:
"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."
Previous research has shown that African Americans are at a 14-times higher risk of colon cancer than rural Africans. This is mostly caused by the American diet, which is too high in animal protein and fats, and too low in fibres.
The good news from this study is that the changes in the African Americans were also quick and evident. Their health visibly improved in days, with biomarkers for colon cancer being significantly reduced.
"I found it very encouraging that just two weeks of dietary changes for the better can bring about changes in health markers that indicate improvements," Amanda Salis, a nutrition and obesity expert from the University of Sydney, who wasn't involved in the study, told Berry at The Age.
However, this was quite a small study, performed with only 20 members from each of the two communities. There's still plenty of work that needs to be done, but there are some significant clues there. Urban diets simply don't involve enough fibers and have too many unhealthy components.
The big takeaway is also clear: eating good or bad foods can change your health - fast.