Vegetarian, vegan and raw diets can be healthy — likely far healthier than the typical American diet. But to continue to call these diets "natural" for humans, in terms of evolution, is a bit of a stretch, according to two recent, independent studies.
Eating meat and cooking food made us human, the studies suggest, enabling the brains of our prehuman ancestors to grow dramatically over a period of a few million years.
Although this isn't the first such assertion from archaeologists and evolutionary biologists, the new studies demonstrate, respectively, that it would have been biologically implausible for humans to evolve such a large brain on a raw, vegan diet and that meat-eating was a crucial element of human evolution at least 1 million years before the dawn of humankind.
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