Here’s a quote from the book The Paleo Diet
“The notion that human beings were meant to be vegetarians runs contrary to every shred of evolutionary evidence from the fossil and anthropological record. We owe a huge debt to lean meat. In fact, scientific evidence overwhelmingly suggests that if our ancient ancestors had eaten a meatless diet, we wouldn’t be where we are today… and we would all look a lot more like our nearest animal relative – the chimpanzee.
How can this be? Chimps are hairy, and they have a big gut. They swing from trees. Well, yes, but about 5 to 7 million years ago, so did our prehuman ancestors. The evidence is that the family tree forks – and humans moved into a category all their own. But genetically speaking, we are only about 1.7 percent different from the chimp.
Chimps are mostly vegetarians (although they do eat a few insects, bird eggs, and the occasional small animal), and they have the big, protruding belly characteristic of vegetarian animals (horses and cows, for example, have big bellies, too). Apes need large active guts to extract the nutrients from their fiber-filled, plant-based diet.
About 2.5 million years ago, our ancestors began trading in their big guts for bigger brains – to the point where today our bellies are about 40 percent smaller than those of chimps and our brains are about three times larger. The turning point came when our ancestors figured out that eating animal food (meat and organs) gave them much more energy. Over the years, their bellies began to shrink because they didn’t need the extra room to process all that roughage. All the energy formerly needed by the gut was diverted to the brain, which doubled and then tripled in size. Without nutrient-dense animal foods in the diet, the large brains that makes us human never would have had the change to develop. Meat and animal foods literally shaped our genome.”
It’s in our DNA, our digestive tract evolved to eat meat, it is healthy to eat meat and a lot of the myths against meat come from the findings related to saturated fats in the 1950s (the ones that come from butter, cheese and fatty meats) which raised cholesterol and increased risk of heart disease, and then this created more of the high carb diets which just fucked us all up.