But aren't most populations in poor developing tropical nations subsisting on traditional diets?
Aren't "traditional" diets supposed to be superior???
And all these tropical populations are OBVIOUSLY super super super healthy, because most of them get LOTS of sun, and therefore their blood Vitamin D levels are super high ---- just open any FR thread about Vitamin D, and you'll learn that lack thereof is responsible for ALL ills, ALL cancers, etc/etc/etc.
Traditional diets are not necessarily healthier than a good modern diet, although they will keep people alive unless something (like the local Communist/Islamic dictatorship) interrupts the food supply.
One of the big lacks in a lot of traditional diets is protein, either because it is actually unavailable (shortage of animal protein) or because it is artificially limited (for example, European peasants being forbidden to hunt game because the landlord wanted it all).