Senior,
You mentioned you were going to ask a family member who has a degree in Anthropology. If you do, be sure you specify the Paleolithic era or any age before agriculture. To play it safe, I would suggest at least 15,000 years ago. If you go back to when people had goats, that wouldn't be far enough.
I'm not sure how true it is but I once read in a Zone book that when ancient Egyptian mummies were studied, they found lots of tooth decay. And they think it was because they ate lots of grain. So it seems that agriculture may have brought with it a host of health issues. I'm not sure about it but it's something to think about.
Perhaps it's okay to eat grain as long as you brush your teeth and get regular dental check ups.
