The Paleolithic Diet says our hunter/gatherer ancestors did not eat grains or nuts. My contention has always been my ancestors ate anything that didn’t eat them first.
Otzi the iceman backs me.
Otzi was killed around 5,300 years ago in the Alps. His body has been studied and photographed and CT-scanned since found in 1991. Scientists say his last meal was: deer meat, herb bread, wheat bran, roots and fruit.
Link at http://www.woodpilereport.com/