I hear a lot about Taubes' theory from people pushing the notion that "we're evolved to eat meat and fruit, not processed grains". I mean, true as far as it goes--but it doesn't go very far. A ribeye and an arugula salad with olive oil and vinegar is almost as far from what our paleolithic ancestors ate as pasta primavera and an angel-food cake. The meat our ancestors ate in the wild was not mostly fat-rich steak—game animals don't have that much body fat, and their muscles are a lot less tender. We've selectively bred our domesticated animals for considerably more succulence than our ancestors enjoyed. In the rich world, we've also stopped eating the "gamier", more vitamin-rich organs. In fact, almost every fruit or vegetable you enjoy eating has been bred to be larger, higher-calorie, and full of less in the way of fibers and natural pesticides than what our pre-agricultural ancestors ate.
Check out her informational graphic about American diets a hundred years ago versus now. Not that much has changed, so ask yourself, what did change?