I agree with a lot of what you say about a healthy diet that includes grains and vegetables. But if eating habits in earlier times were so superior to our current diet, why was life expectancy 26 years in the Bronze age, 30 in pre-Columbian Southern U.S., 40 in early 19th century England, and in 1900 the world average was 31 whereas in 2017 it was 72.2.

I realize infant mortality was extremely high and there were many diseases without antibiotics, vaccines, etc. But all these things taken together make me look with some skepticism at the prevailing belief that whatever we do in modern society is inferior to some glorified but nonexistent past.