You won't catch John Durant in a tie. Shoes are optional, too. He has traded cubicle life for something a little wild: Promoting the diet and lifestyle of our ancestors from the paleolithic era. He's blogging and writing a book about his approach.

"For millions of years, we didn't have an obesity problem because we ate foods that our metabolism was adapted to," Durant says — foods such as root vegetables, tubers, fish and, of course, red meat.

"We were active and lived a healthy lifestyle," he says. Durant is one of many folks following the popular meat-laden paleo diet. He packs his freezer with deer meat and has found lots of places near his home in Manhattan to buy marrow bones and organ meats, as well as paleo-friendly barbecue joints for a meal out.

But modern medicine tells us that too much meat is bad for us, so what's a consumer to do?

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