Paleo diet - BBC news, Researchers found Neanderthal's teeth had cooked and uncooked grains. Neanderthal sites had large amounts of pollen, type not discernible. For the current definition of "forager" diet three groups have been studied in Africa still practicing their traditional living. On one of them, perhaps 70% of the diet is plant foods much gathered by women (a kid on one hip, another walking beside) also men. Discussion with one of the men about worldwide problems of food shortage he said (approximate) "How can that be. There are so many Lichi (sic) nuts in (his) world." The men try to catch some (very) lean meat with intermittent success. They are fit, lean, women nurse 3 years have a child once maybe every 4 or 5 years. Very healthy looking people. My impression from the article, they had enough plant food did some animal food just for taste. Another area for investigation might be the Australian natives highly successful at bush tucker.
All this is interesting in implications of what people evolved with over 4 million years. Physiologically we do very well with plant foods. People are prone to addictions and may have a taste for animal foods. We're vegans, in our 70's, no meds, my wife triathlons and I bicycle, BMI just fine.