Our paleolithic ancestors didn't drink milk, for example, because they lacked the ability to process it upon reaching adulthood. Several different mutations have arisen since then allowing humans to digest milk, and they've spread throughout many global populations, rendering a great number of adults able to digest milk as adults.

Really?

I've never heard about Paleo diet until last year when I was researching for Ketogenic diet. Even though I knew the concept of Paleo diet, I've never used them as I didn't fully understand it.