Black, it goes back a whole lot further than the Native Americans. Humans evolved eating protein. We have millions of years of evolution devoted to eating protein as our main food source. It's only been in the past 10,000 years that people started relying on grain sources. That's not nearly long enough for the human body to make the necessary evolutionary changes for us to extract our vital nutrients from grain.

Studies have been done on Australian Aborigines. Living in the wild, they enjoy good health because of their naturally low-carb diets. When they are subjected to a modern high-carb diet, they quickly develop severe insulin resistance. Just a few weeks back in the wild and they reverse these disorders.

If you're interested, and it sounds like you are, I urge you to read the books "Protein Power" and "Protein Power Lifeplan." The Drs. Eades tell all kinds of interesting facts like this. Another example is early humans. Prior to agriculture, human bones are thick and strong, the people were taller, their teeth had virtually no sign of decay. Enter agriculture, and it's a different story. Studies of Egyptian mummies show brittle bones, arthritis (for the first time in the historical record), decayed teeth and teeth worn down past the enamel because of the grain-based diet.

The more you read, the more you'll be convinced that this is the way we should be eating.