Basic foodstuffs like rice, corn, wheat, potatoes, oats, nuts, fruits, veggies have been the basis for human diet throughout millions of years.
It's only that last hundred years or so that science figured out a way to (1) preserve food and (2) make it taste better. Stay away from processed foods and you're 50% the way there.
Eat meat about as regularly as our ancestors did ie stumbling across a dead dear and having a feast, then back to hunting and pecking.
I will readily admit I'm not the world's expert on this but that's not what I read. Cereals have not been around in quantity since after 6000 B.C. or so. Most of those millions of years our diets were not as heavily carbohydratic (is that a word?) as they are today.
Eat meat about as regularly as our ancestors did ie stumbling across a dead dear and having a feast, then back to hunting and pecking.
It is my understanding that caveman got about 65% of his calories from protein.