An analysis of fossilized Native American feces shows that our ancestors ate up to sixteen times the fiber that we do today, but our stomachs didn’t evolve to fit our changing diets.
The findings come from analysis of fossilized feces dating from A.D 1123 and earlier. They reveal that the ancient Native Americans lived on a heavily fibrous diet of prickly pear, yucca, and seeds, with low impact on blood sugar.
The native people of Arizona ate foods with traditionally very low glycemic indexes, but are now more susceptible to type 2 diabetes than Caucasians, for their bodies do not produce enough insulin to break down the sugar in modern foods. The Native populations were extremely efficient in their calorie intake, but the arrival of Europeans caused their diet to change faster than their bodies could keep up with, and their digestive systems didn’t evolve to handle foods with a high glycemic index.
Modern humans of all ethnicities have suffered from this dietary change.