With a very simple shift we not only remove the foods that are at odds with our health (grains, legumes, and dairy) but we also increase our intake of vitamins, minerals, and antioxidants. Here is a great paper from Professor Loren Cordain exploring how to build a modern Paleo diet: The nutritional characteristics of a contemporary diet based upon Paleolithic food groups. This paper also offers significant insight as to the amounts and ratios of protein, carbohydrate and fat in the ancestral diet.
The Paleolithic or “Paleo” diet seeks to address 21st century ills by revisiting the way humans ate during the Paleolithic era more than 2 million years ago. Paleo proponents state that because our genetics and anatomy have changed very little since the Stone Age, we should eat foods available during that time to promote good health. Our predecessors used simple stone tools that were not advanced enough to grow and cultivate plants, so they hunted, fished, and gathered wild plants for food. If they lived long enough, they were believed to experience less modern-day diseases like diabetes, cancer, and heart disease because of a consistent diet of lean meats and plant foods along with a high level of physical activity from intensive hunting. However, the life expectancy of our predecessors was only a fraction of that of people today.
This 2003 CrossFit Journal article captures an early conception of a universal, multi-event test of fitness that laid the foundation for CrossFit competition, including what would become the CrossFit Open and the CrossFit Games. The design requirements for such a test "included but were not limited to the following: quantifiable results; consistency with the CrossFit fitness concept; raising our commitment to improving absolute strength, relative strength, and gymnastic foundations; balancing intrinsic abilities of smaller and larger athletes; emphasizing exercises critical to and foundational to advanced training; mixing training demands within each test and, of course, over the total competition; a design that would identify an athlete’s weaknesses and possibly stand as a workout plan for improving overall fitness; and, finally, we wanted to design a competition that would be 'hard as hell.'"