Fifteen indigenous Africans from rural areas of the continent ate the typical American diet for two weeks; and for 15 days a group of Americans ate like Africans from rural tribes. The results, encapsulated in one study, are downright shocking.
In fact, in the two weeks in which a group of African Americans followed a traditional African diet typical of rural areas, its biomarkers of cancer risk were considerably reduced; in particular, the risk of colorectal neoplasia was reduced, and a substantial modification of the microbiota was observed.

As per previous studies, it seems that the intestinal bacterial flora improves significantly in a few days , already allowing better health after a few weeks of dietary change. In particular, the Americans in the study ate a diet with a high consumption of low glycemic index carbohydrates (legumes, tubers, whole grains), a moderate consumption of proteins and a low consumption of fat.
But the researchers also did the reverse game, giving a group of Africans the opportunity to experiment with the Western diet, with particular reference to the American diet: fast food, fried food, for just two weeks.
The results? A deterioration in health, a tendency to gain weight and a diseased bacterial flora, with biomarkers of neoplastic risk.
Researchers therefore have no doubts: a diet rich in bad fats and low-nutrient foods with a high glycemic index, with a lack of fiber and vegetables, makes the bacterial flora sick, makes us fatter and exposed to serious diseases.
But we can change our health picture in no time: just eat more fruit and vegetables, choose simple cooking, and tubers and whole grains instead of less healthy alternatives like baked goods and snacks.